Depends on the strain (some produce some really nasty toxins), and who's getting it. Some E. coli is harmless, and lives commensally in your gut, helping you digest your food.
On the other hand, enterohaemorrhagic E. coli O157:H7 (EHEC) can give you acute kidney failure, and has killed children and old people whose immune systems weren't strong enough.
I started using Linux on my desktop full time back in 2002. I've currently got the latest Linux Mint installed, and it's a dream to use. When I started using a Mac for work in 2012, I found the OS rather frustrating to use, and have done much tinkering to make it more like Linux again.
As far as I'm concerned, either Linux has been ready for the desktop for a very long time already, or being ready for the desktop is some unattainable status that so far no OSes have managed.
I find OS X's window manager quite clunky, and I appreciate being able to Opt-Space to pull down an iTerm2 on any desktop, especially as you can open any file with Cmd-Click, I'm faster using iTerm2 than with the Finder.
However on Linux (Mint Cinnamon, which I like very much), I just type Super-A, and a terminal pops up wherever I am, so I don't need the Quake-style drop-down. I don't use Windows, so I don't have a solution there.
I work as a mathematical epidemiologist, modelling disease spread in populations. In my work there are three cases when I encounter divide by zero.
1) Disease transmission. Say you have two types of individual, susceptible and infectious, the numbers of which are given by S(t) and I(t), and the total population size is N=S+I. Diseases typically transmits at a rate beta*S*I/N, where beta is the transmission coefficient. What happens when N=0? In this case we want the transmission rate to also be 0.
2) Poisson distributed random numbers. When events happen randomly at rate lambda, the number of events that occur in a time interval dt is n~Poisson(lambda*dt). When lambda=0, you'd always expect n=0. Strictly speaking the Poisson distribution isn't defined for lambda=0, but the limit as lambda->0 is indeed 0. The GNU Scientific Library, Octave, Matlab, and R all return 0 for Poisson(0), however Julia and Numpy both return an error.
3) Adaptive tau leaping. If you aren't using fixed tau leaping, then you need to work out how big a time step you can safely take, which requires bounding the relative change in a variable. This is done by dividing the variable size by the expected change in that variable, and finding the time step tau, repeating for every variable, and taking the smallest time step you get. In this case, it is entirely possible that the expected time step is zero, say when the population is at equilibrium. This doesn't mean that nothing is happening (you should also check that the variance is bounded), and so here you absolutely need that divide by zero is infinity, and that infinity is greater than any other number you might find.
The first two cases are actually undefined (0/0 is mathematically undefined, since you get different answers depending on how you approach the limit), but the desired outcome is clearly zero. The third case is either 0/0 or x/0, but either way you definitely want to interpret the result as infinity.
In my situation, I just wrote a small function called div0, which I use whenever I expect a divide by zero to occur, and know that I want to interpret that as zero, not infinity.
As a mathematician and scientist living in Scotland, I lament our use of decimal. Counting in base-12 would have been considerably more useful. Frankly I think we divide by 5 far less often than we divide by 2, 3, 4, or 6, and only one of those gives a round number in decimal. As for the convenience of having 10 fingers, we also have 12 finger segments, allowing us to count to 144 (100 in base 12) on our fingers.
But then imperial measurements are often not based on units of 12. There may be 12 inches in a foot, there are 3 feet in a yard, 16 ounces in a pound, 14 pounds in a stone, 20 ounces in a pint, 8 pints in a gallon, gods know how many feet in a mile, 3 miles in a league... and I only know a few of those without looking them up.
Really, basing everything around one number is such a convenience, even if those numbers aren't always wholly convenient for having day-to-day things ending up in integer numbers.
I use Cherry MX browns at work, and MX blues at home. I hugely prefer the blues. The audible click is satisfying, but the tactile feel is just so much better. I haven't tried MX clears yet (strongly tactile, quiet), but I think they would be better off for my work keyboard.
Whenever I see a Windows desktop with file extensions disabled, I always try to explain to the person that they should be switched back on, and most people are quite happy to do so (they only had them off because that was the default).
However I was quite dismayed when I looked at my mother's laptop (which I had installed Linux Mint on for her), and she had no file extensions either. It turned out that she thought they looked untidy, and had gone through and manually removed the extensions from every single file in her home directory!
Fortunately the file and mmv commands made short work of fixing this, but I was surprised to say the least.
I'm 32, and in my whole life I've only seen a few guns in the UK. There were some air rifles in my school rifle club, and a couple of guns when I was in the ATC as a teenager. I don't know anyone who admits to owning a gun. I visited the US for 5 weeks when I was 15, and saw loads of them (I found it incredibly intimidating).
A very cursory check suggests that there are around 1.8 million guns in the UK, mostly in rural areas. That's 1 for every 35 people. So yes, there may be some guns, but the UK is a different situation to the US.
At the risk of going against the general feeling, here in the UK we don't have any guns, and we have remarkably few school shootings. I honestly don't think that bringing more guns to the mix would make us safer. Yes, there are knife attacks, but it's considerably harder to kill people with a knife than with a gun, and running away is a realistic solution.
However the US has the problem that it already tolerates guns, so you need to find a different solution. Bringing more guns to the mix is going to make things safer. Stopping people having them in the first place would be a more sensible approach, but the 2nd amendment prevents that. This is not trolling or flamebait, but I personally find it very hard to justify that law: overthrowing a bad government would take more than just shooting a bunch of old men in the White House, you'd need to take on the military, and they have tanks, so you'll keep on having children dying as the years drag on for no appreciable benefit.
I really hope that the US can find a way to help troubled kids, to make it so they don't feel that the only option to get noticed is to kill the people around them, and the only solution at that point is to kill them before they kill to many others, but I don't think the system is set up that way.
That would be awful. Your system would immediately hurt poor people, and benefit rich people, and since poor people vastly outnumber the rich, you'll end up harming the economy too, both through huge numbers of people buying less because they're worse off, and rich people paying less.
Taxing necessities the same as luxuries also hits poor people more, as they rely on the former. You need *progressive* taxation to account for people's ability to pay, since a flat tax for a poor person hurts much more than the same amount for a rich person.
Taxes are also there to penalise harmful activities. For example, there is a huge tax on tobacco that pays for treatment of cigarette smokers 5 times over (in the UK at least, I'm guessing you're from the US if you have hospital bills). Losing that would be a huge hit to medical care. Similarly, there are taxes on fuel and carbon usage to help prevent air pollution, since global warming is a huge problem that we face (okay, we'll ignore that state that decided to tax fuel efficient cars to make up for lost income, that was just stupid).
When I use onboard sound, there's a slight crackly hissing noise that happens when I move the mouse, which I can hear whenever the speaker volume is more than about 50%. It was true for my old PC that I bought 6 years ago, and it's true for the one I bought last month.
From my sample size of 2, it's definitely a problem. Sure the sound quality is fine, but I think there's still a case for a discrete card.
Oops, typo -- it's one of my favourite ales too. Don't worry, I've lived in Scotland most of my life, and I most certainly don't confuse England with the UK! However, the taste / temperature issue applies to Scottish beers too, and it was a general statement. I certainly don't discriminate when it comes to good beer!
England should let them go and concentrate their efforts instead, on making a beer that's worth a fuck.
Nothing wrong with English beers, there are a great many excellent ones, and many interesting regional ones to be found. The UK does good beer -- go and find a bottle of Norfolk Nog, and tell me it doesn't taste wonderful, or try a bottle of Fraioch heather ale, and note how refreshing it is.
It might be the case that you're too used to crap beer that needs to be chilled in order to taste okay. Good beer isn't supposed to be served warm, just cool, because you're meant to be able to taste it.
Socialism doesn't keep you at work, when you're sick, that's capitalism, with its "performance at the expense of everything else" approach. Or were you being sarcastic? (I can't tell).
Also, socialism provides free medical care to sick people, so they don't just put things off and get worse and worse until eventually they eventually either need an emergency room (at a much higher cost), or spread communicable but treatable diseases like TB. It also makes medicine cheaper because of collective bargaining, rather than allowing each person to try to bargain for something that they can't do without.
I use Octave and totally ignore Matlab compatibility. This enables me to use the (IMO vastly superior) Octave syntax additions. On the odd occasion I need to go back to Matlab, I find the syntax incredibly restrictive. Small things like ++i, default parameters, and temporary expressions, all of which make life so much easier. I understand why this situation exists, but I think it's a terrible shame.
Then there's Octave's ASCII format for storing structures and multidimensional (>2 dim) arrays. That single feature alone is why I don't use Matlab.
I was at the recent Elsevier Epidemics 4 conference (a good conference by the way, they've discussed many important things and highlighted a lot of important work), and they noted that despite growing attendance over the last few years, they've received fewer and fewer submissions to their Epidemics journal, despite it being Open Access. I suspect the boycott is indeed starting to bite.
It's been the year of Linux on the desktop for me since around 2003, when the guys I shared a flat with deliberately set the anime server so windows users couldn't access it (I was dual booting at the time, and decided I didn't really need to stay in Windows any more).
Nowadays I'm a postdoc research assistant working in mathematical epidemiology; I do a lot of programming and writing (mostly in LaTeX), most people at work use Linux, and having it at work and home makes my life very easy.
Yes, there's occasionally a game I can't play under Linux that wine can't handle, so I do still have a partition for Windows, but I'm now so unused to Windows that it feels alien and clunky, and I miss all the features I've become accustomed too. Given how it can be just as difficult to fix problems when they occur in Windows, if it weren't for Windows massive market share, I'd question if it were ready for the desktop yet.
Your opinion as a non-scientist on the matter is of course equally valid as that of an expert in the field.
That said, it's fine to comment on why you think the experts may have conflicting interests (this sort of information must be declared in any scientific papers they publish).
So you spent the last ten years looking at the cool Linux screen savers?
No, the usual stuff: playing Minecraft, watching DVDs and other videos (we don't have a TV), spending ages on the Internet, and catching up on work. My wife uses it for those things too (except she prefers Plants vs Zombies to Minecraft).
Eh, I really liked GNOME towards the end of its version 2 cycle. The Mac OS ness didn't bother me at all, I thought it looked great and was really easy and nice to use. I've recently started using a Mac for work, and I'm pretty disappointed at how unimpressive it is in comparison. The way OS X handles multiple desktops seems like a total regression.
That funny row/column order in matrix indices (aka column major order) is because it's the correct mathematical order.
Consider that you can only multiply two matrices if matrix A is of size [i,j], and matrix B is of size [j,k], i.e. the number of rows in A must be equal to the number of columns in B. The product C=AB is then of size [i,k]. This works for any number of matrices, so, [i,j]*[j,k]*[k,l]*[l,m] is valid, and gives [i,m].
This naturally leads to the indexing you see in Fortran and Matlab, because it's the way mathematicians like it. If you had row major order, then [j,i]*[k,j]=[k,i], which is pretty horrible in comparison.
Thanks for the link. My problem is that there isn't any one bit you can point to and say "that's the slow bit" (unless it's telling the code which parameters to use, varying the parameters, and then graphing the results when done -- I'm currently doing those parts with bash and Octave, and to be fair I would probably be better off doing both of those in Python).
The main work is the simulation, and it's where I've got a trivially small amount of data (say a 20x20 lattice of sites containing the number of susceptible and infective animals), so I need arrays to store the numbers of individuals, the birth, death, infection, recovery, dispersal rates for each site, and one that keeps track of which sites need updating.
The bits you might think would be the slow bits (summing arrays, checking there are no groups with negative numbers of individuals, converting rate matrices into cumulative distribution functions and using a binary search to select an event) just don't seem to have that much of an effect on the performance. The only time that a part significantly stands out is when calculating dispersal across the entire lattice, rather than a nearest neighbour dispersal. The rest is just lots of small things that need to be done randomly and frequently.
I have profiled the model quite a bit, and the C code is over 300 times faster than the prototype written in Octave (taking advantage of vectorisation whenever possible, and using fast algorithms), but all the non-performance critical bits are either deeply embedded in the code (which is horrifically loopy by nature of the problem), or necessary for the rest to work. So Python isn't really going to help.
Sadly, with the exception of a few times where I get to sum an array, pretty much my whole model needs to be run in a fast language like C or Fortran (I use C, my supervisor uses F77). It's the kind of model (a spatial stochastic disease simulation) that doesn't really lend itself to coding up in Python. No matrices, just lots of little bits of data interrogation, calculating one event at a time, and so many loops (unavoidable) that it would just crawl in Python. If you try to start in Python and replace the slow bits with C, then before you know it it's more C than Python. In the end, I think doing the whole thing in C is just less work.
I do all the graphs, and the non-spatial deterministic versions in Octave (R's graphs are prettier, but R is less pleasant to use), where it does take advantage of Fortran for the ODE solver, but that's the only bit. I do generally prefer the 1-based array indexing though, the only places I've found 0-based indexing useful has been dealing with C's inability to handle multidimensional variable length arrays in an easy fashion, so I wasn't really convinced by 0-based arrays in general. Perhaps I'd have been better off with Fortran, but that's just the way it turned out.
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Depends on the strain (some produce some really nasty toxins), and who's getting it. Some E. coli is harmless, and lives commensally in your gut, helping you digest your food.
On the other hand, enterohaemorrhagic E. coli O157:H7 (EHEC) can give you acute kidney failure, and has killed children and old people whose immune systems weren't strong enough.
I started using Linux on my desktop full time back in 2002. I've currently got the latest Linux Mint installed, and it's a dream to use. When I started using a Mac for work in 2012, I found the OS rather frustrating to use, and have done much tinkering to make it more like Linux again.
As far as I'm concerned, either Linux has been ready for the desktop for a very long time already, or being ready for the desktop is some unattainable status that so far no OSes have managed.
I find OS X's window manager quite clunky, and I appreciate being able to Opt-Space to pull down an iTerm2 on any desktop, especially as you can open any file with Cmd-Click, I'm faster using iTerm2 than with the Finder.
However on Linux (Mint Cinnamon, which I like very much), I just type Super-A, and a terminal pops up wherever I am, so I don't need the Quake-style drop-down. I don't use Windows, so I don't have a solution there.
I work as a mathematical epidemiologist, modelling disease spread in populations. In my work there are three cases when I encounter divide by zero.
1) Disease transmission. Say you have two types of individual, susceptible and infectious, the numbers of which are given by S(t) and I(t), and the total population size is N=S+I. Diseases typically transmits at a rate beta*S*I/N, where beta is the transmission coefficient. What happens when N=0? In this case we want the transmission rate to also be 0.
2) Poisson distributed random numbers. When events happen randomly at rate lambda, the number of events that occur in a time interval dt is n~Poisson(lambda*dt). When lambda=0, you'd always expect n=0. Strictly speaking the Poisson distribution isn't defined for lambda=0, but the limit as lambda->0 is indeed 0. The GNU Scientific Library, Octave, Matlab, and R all return 0 for Poisson(0), however Julia and Numpy both return an error.
3) Adaptive tau leaping. If you aren't using fixed tau leaping, then you need to work out how big a time step you can safely take, which requires bounding the relative change in a variable. This is done by dividing the variable size by the expected change in that variable, and finding the time step tau, repeating for every variable, and taking the smallest time step you get. In this case, it is entirely possible that the expected time step is zero, say when the population is at equilibrium. This doesn't mean that nothing is happening (you should also check that the variance is bounded), and so here you absolutely need that divide by zero is infinity, and that infinity is greater than any other number you might find.
The first two cases are actually undefined (0/0 is mathematically undefined, since you get different answers depending on how you approach the limit), but the desired outcome is clearly zero. The third case is either 0/0 or x/0, but either way you definitely want to interpret the result as infinity.
In my situation, I just wrote a small function called div0, which I use whenever I expect a divide by zero to occur, and know that I want to interpret that as zero, not infinity.
As a mathematician and scientist living in Scotland, I lament our use of decimal. Counting in base-12 would have been considerably more useful. Frankly I think we divide by 5 far less often than we divide by 2, 3, 4, or 6, and only one of those gives a round number in decimal. As for the convenience of having 10 fingers, we also have 12 finger segments, allowing us to count to 144 (100 in base 12) on our fingers.
But then imperial measurements are often not based on units of 12. There may be 12 inches in a foot, there are 3 feet in a yard, 16 ounces in a pound, 14 pounds in a stone, 20 ounces in a pint, 8 pints in a gallon, gods know how many feet in a mile, 3 miles in a league... and I only know a few of those without looking them up.
Really, basing everything around one number is such a convenience, even if those numbers aren't always wholly convenient for having day-to-day things ending up in integer numbers.
I use Cherry MX browns at work, and MX blues at home. I hugely prefer the blues. The audible click is satisfying, but the tactile feel is just so much better. I haven't tried MX clears yet (strongly tactile, quiet), but I think they would be better off for my work keyboard.
Whenever I see a Windows desktop with file extensions disabled, I always try to explain to the person that they should be switched back on, and most people are quite happy to do so (they only had them off because that was the default).
However I was quite dismayed when I looked at my mother's laptop (which I had installed Linux Mint on for her), and she had no file extensions either. It turned out that she thought they looked untidy, and had gone through and manually removed the extensions from every single file in her home directory!
Fortunately the file and mmv commands made short work of fixing this, but I was surprised to say the least.
I'm 32, and in my whole life I've only seen a few guns in the UK. There were some air rifles in my school rifle club, and a couple of guns when I was in the ATC as a teenager. I don't know anyone who admits to owning a gun. I visited the US for 5 weeks when I was 15, and saw loads of them (I found it incredibly intimidating).
A very cursory check suggests that there are around 1.8 million guns in the UK, mostly in rural areas. That's 1 for every 35 people. So yes, there may be some guns, but the UK is a different situation to the US.
At the risk of going against the general feeling, here in the UK we don't have any guns, and we have remarkably few school shootings. I honestly don't think that bringing more guns to the mix would make us safer. Yes, there are knife attacks, but it's considerably harder to kill people with a knife than with a gun, and running away is a realistic solution.
However the US has the problem that it already tolerates guns, so you need to find a different solution. Bringing more guns to the mix is going to make things safer. Stopping people having them in the first place would be a more sensible approach, but the 2nd amendment prevents that. This is not trolling or flamebait, but I personally find it very hard to justify that law: overthrowing a bad government would take more than just shooting a bunch of old men in the White House, you'd need to take on the military, and they have tanks, so you'll keep on having children dying as the years drag on for no appreciable benefit.
I really hope that the US can find a way to help troubled kids, to make it so they don't feel that the only option to get noticed is to kill the people around them, and the only solution at that point is to kill them before they kill to many others, but I don't think the system is set up that way.
That would be awful. Your system would immediately hurt poor people, and benefit rich people, and since poor people vastly outnumber the rich, you'll end up harming the economy too, both through huge numbers of people buying less because they're worse off, and rich people paying less.
Taxing necessities the same as luxuries also hits poor people more, as they rely on the former. You need *progressive* taxation to account for people's ability to pay, since a flat tax for a poor person hurts much more than the same amount for a rich person.
Taxes are also there to penalise harmful activities. For example, there is a huge tax on tobacco that pays for treatment of cigarette smokers 5 times over (in the UK at least, I'm guessing you're from the US if you have hospital bills). Losing that would be a huge hit to medical care. Similarly, there are taxes on fuel and carbon usage to help prevent air pollution, since global warming is a huge problem that we face (okay, we'll ignore that state that decided to tax fuel efficient cars to make up for lost income, that was just stupid).
When I use onboard sound, there's a slight crackly hissing noise that happens when I move the mouse, which I can hear whenever the speaker volume is more than about 50%. It was true for my old PC that I bought 6 years ago, and it's true for the one I bought last month.
From my sample size of 2, it's definitely a problem. Sure the sound quality is fine, but I think there's still a case for a discrete card.
Oops, typo -- it's one of my favourite ales too. Don't worry, I've lived in Scotland most of my life, and I most certainly don't confuse England with the UK! However, the taste / temperature issue applies to Scottish beers too, and it was a general statement. I certainly don't discriminate when it comes to good beer!
England should let them go and concentrate their efforts instead, on making a beer that's worth a fuck.
Nothing wrong with English beers, there are a great many excellent ones, and many interesting regional ones to be found. The UK does good beer -- go and find a bottle of Norfolk Nog, and tell me it doesn't taste wonderful, or try a bottle of Fraioch heather ale, and note how refreshing it is.
It might be the case that you're too used to crap beer that needs to be chilled in order to taste okay. Good beer isn't supposed to be served warm, just cool, because you're meant to be able to taste it.
Socialism doesn't keep you at work, when you're sick, that's capitalism, with its "performance at the expense of everything else" approach. Or were you being sarcastic? (I can't tell).
Also, socialism provides free medical care to sick people, so they don't just put things off and get worse and worse until eventually they eventually either need an emergency room (at a much higher cost), or spread communicable but treatable diseases like TB. It also makes medicine cheaper because of collective bargaining, rather than allowing each person to try to bargain for something that they can't do without.
I've had half a lifetime since I got my 6 digit ID.
I use Octave and totally ignore Matlab compatibility. This enables me to use the (IMO vastly superior) Octave syntax additions. On the odd occasion I need to go back to Matlab, I find the syntax incredibly restrictive. Small things like ++i, default parameters, and temporary expressions, all of which make life so much easier. I understand why this situation exists, but I think it's a terrible shame.
Then there's Octave's ASCII format for storing structures and multidimensional (>2 dim) arrays. That single feature alone is why I don't use Matlab.
I was at the recent Elsevier Epidemics 4 conference (a good conference by the way, they've discussed many important things and highlighted a lot of important work), and they noted that despite growing attendance over the last few years, they've received fewer and fewer submissions to their Epidemics journal, despite it being Open Access. I suspect the boycott is indeed starting to bite.
It's been the year of Linux on the desktop for me since around 2003, when the guys I shared a flat with deliberately set the anime server so windows users couldn't access it (I was dual booting at the time, and decided I didn't really need to stay in Windows any more).
Nowadays I'm a postdoc research assistant working in mathematical epidemiology; I do a lot of programming and writing (mostly in LaTeX), most people at work use Linux, and having it at work and home makes my life very easy.
Yes, there's occasionally a game I can't play under Linux that wine can't handle, so I do still have a partition for Windows, but I'm now so unused to Windows that it feels alien and clunky, and I miss all the features I've become accustomed too. Given how it can be just as difficult to fix problems when they occur in Windows, if it weren't for Windows massive market share, I'd question if it were ready for the desktop yet.
Your opinion as a non-scientist on the matter is of course equally valid as that of an expert in the field.
That said, it's fine to comment on why you think the experts may have conflicting interests (this sort of information must be declared in any scientific papers they publish).
So you spent the last ten years looking at the cool Linux screen savers?
No, the usual stuff: playing Minecraft, watching DVDs and other videos (we don't have a TV), spending ages on the Internet, and catching up on work. My wife uses it for those things too (except she prefers Plants vs Zombies to Minecraft).
2003 was the year of Linux on the Desktop for me. Has been ever since too.
Eh, I really liked GNOME towards the end of its version 2 cycle. The Mac OS ness didn't bother me at all, I thought it looked great and was really easy and nice to use. I've recently started using a Mac for work, and I'm pretty disappointed at how unimpressive it is in comparison. The way OS X handles multiple desktops seems like a total regression.
That funny row/column order in matrix indices (aka column major order) is because it's the correct mathematical order.
Consider that you can only multiply two matrices if matrix A is of size [i,j], and matrix B is of size [j,k], i.e. the number of rows in A must be equal to the number of columns in B. The product C=AB is then of size [i,k]. This works for any number of matrices, so, [i,j]*[j,k]*[k,l]*[l,m] is valid, and gives [i,m].
This naturally leads to the indexing you see in Fortran and Matlab, because it's the way mathematicians like it. If you had row major order, then [j,i]*[k,j]=[k,i], which is pretty horrible in comparison.
Thanks for the link. My problem is that there isn't any one bit you can point to and say "that's the slow bit" (unless it's telling the code which parameters to use, varying the parameters, and then graphing the results when done -- I'm currently doing those parts with bash and Octave, and to be fair I would probably be better off doing both of those in Python).
The main work is the simulation, and it's where I've got a trivially small amount of data (say a 20x20 lattice of sites containing the number of susceptible and infective animals), so I need arrays to store the numbers of individuals, the birth, death, infection, recovery, dispersal rates for each site, and one that keeps track of which sites need updating.
The bits you might think would be the slow bits (summing arrays, checking there are no groups with negative numbers of individuals, converting rate matrices into cumulative distribution functions and using a binary search to select an event) just don't seem to have that much of an effect on the performance. The only time that a part significantly stands out is when calculating dispersal across the entire lattice, rather than a nearest neighbour dispersal. The rest is just lots of small things that need to be done randomly and frequently.
I have profiled the model quite a bit, and the C code is over 300 times faster than the prototype written in Octave (taking advantage of vectorisation whenever possible, and using fast algorithms), but all the non-performance critical bits are either deeply embedded in the code (which is horrifically loopy by nature of the problem), or necessary for the rest to work. So Python isn't really going to help.
Sadly, with the exception of a few times where I get to sum an array, pretty much my whole model needs to be run in a fast language like C or Fortran (I use C, my supervisor uses F77). It's the kind of model (a spatial stochastic disease simulation) that doesn't really lend itself to coding up in Python. No matrices, just lots of little bits of data interrogation, calculating one event at a time, and so many loops (unavoidable) that it would just crawl in Python. If you try to start in Python and replace the slow bits with C, then before you know it it's more C than Python. In the end, I think doing the whole thing in C is just less work.
I do all the graphs, and the non-spatial deterministic versions in Octave (R's graphs are prettier, but R is less pleasant to use), where it does take advantage of Fortran for the ODE solver, but that's the only bit. I do generally prefer the 1-based array indexing though, the only places I've found 0-based indexing useful has been dealing with C's inability to handle multidimensional variable length arrays in an easy fashion, so I wasn't really convinced by 0-based arrays in general. Perhaps I'd have been better off with Fortran, but that's just the way it turned out.