• ### Math function to shift fractional digits left of decimal point?

I need a math function that can shift the digits to the right of the decimal point onto the left side of the decimal point. I don't know if one exists. is there one? what is it? where can I find documentation on it? does it have a symbol instead of a function? I would prefer a function or something I can implement as a function if... show more
I need a math function that can shift the digits to the right of the decimal point onto the left side of the decimal point. I don't know if one exists. is there one? what is it? where can I find documentation on it? does it have a symbol instead of a function? I would prefer a function or something I can implement as a function if possible. really what I am trying to do is figure out the number of fractional digits, and I have (ttcalc): ceil(log( 1+int(abs(frac(511.))) ;10)/log(10;10)) but it is failing miserably. tried 10^x just throwing stuff around to see what might work.
1 answer · Mathematics · 4 years ago
• ### MTTF of today's chips, circuit boards given metal migration?

what is the MTTF of today's chips and boards with metal migration?
what is the MTTF of today's chips and boards with metal migration?
1 answer · Engineering · 4 years ago

I am trying to do LED beam projection calculations. to do this, I need to calculate the steradians of a cone given the radius, and angle in radians. if I need more info than that, please let me know. thanks. I would assume the radius would be dimensionless.
I am trying to do LED beam projection calculations. to do this, I need to calculate the steradians of a cone given the radius, and angle in radians. if I need more info than that, please let me know. thanks. I would assume the radius would be dimensionless.
3 answers · Mathematics · 4 years ago
• ### How long do LED,LCD monitors last?

how long do LED monitors last? how long do LCD monitors last? if you know, what usually goes wrong with them? (CFL,PSU, capacitor, LCD, LED,driver circuitry, chips) I have a friend who had a flat panel display (don't know if it was an LCD or LED) and it lasted the length of the warranty - failed due to power supply capacitor). he ended up... show more
how long do LED monitors last? how long do LCD monitors last? if you know, what usually goes wrong with them? (CFL,PSU, capacitor, LCD, LED,driver circuitry, chips) I have a friend who had a flat panel display (don't know if it was an LCD or LED) and it lasted the length of the warranty - failed due to power supply capacitor). he ended up buying a new monitor. IF it is just the power supply that usually goes out (my psu is separate), I figure I can order a new power adapter from the company that made the monitor. if I am forced to, I can MAYBE splice one together from newark.com using the existing power connector cable (so I have the right connector). a little heat shrink tubing, solder, soldering iron, wire cutters, wire strippers, ohmmeter/DMM to tell which wires go to which part of the connector, and away we go...
2 answers · Monitors · 5 years ago
• ### What exactly determines whether a video card will work with a motherboard and cpu?

is it simply the number of PCI express lanes that the CPU supports? for instance, the i7-3970x supports 40. but how many exactly does say, an nvidia/pny/hp/dell quadro fx 4000 video card use? 16? http://www.nvidia.com/object/product-quadro-4000-us.html PCI Express 2.0 x16 how many lanes are used by the rest of the mobo on internal peripherals, if... show more
is it simply the number of PCI express lanes that the CPU supports? for instance, the i7-3970x supports 40. but how many exactly does say, an nvidia/pny/hp/dell quadro fx 4000 video card use? 16? http://www.nvidia.com/object/product-qua... PCI Express 2.0 x16 how many lanes are used by the rest of the mobo on internal peripherals, if any? or is the determining factor the GPU clock speed? or is it the gpu clock speed combined with the number of cores that you have to somehow match with either the cpu or cpu and mobo (specifically, what on the mobo?)? is there something I am missing?
1 answer · Desktops · 5 years ago
• ### Any issues with buying a used quadro video card from ebay?

any issues with buying a used quadro video card from ebay? I was looking at maybe something like - 1 PNY or HP quadro FX 4000 or FX 4800 [workstation] video card. - adobe cs5 (all of it) - 1 asus p9x79 deluxe motherboard (will this be sufficient,or am I supposed to be getting the p9x79 ws instead for use that video card for the increased bus... show more
any issues with buying a used quadro video card from ebay? I was looking at maybe something like - 1 PNY or HP quadro FX 4000 or FX 4800 [workstation] video card. - adobe cs5 (all of it) - 1 asus p9x79 deluxe motherboard (will this be sufficient,or am I supposed to be getting the p9x79 ws instead for use that video card for the increased bus speed?) - 1 i7-3970x proc (should be fast enough) only issue I could think of was maybe the fan's lifespan. I also need to know if all this will work together well. if I should skip it and buy new, I need some reasons. I am trying to save some money if possible. the system is going to have to work for a long time, so I hope the card (meaning the fan at least) is serviceable. I assume the point of failure would most likely be the moving parts first (even with proper maintenance like cleaning or maybe even lubing) - I have no clue what the life expectancy is of the PNY vs. HP cards.
5 answers · Desktops · 5 years ago
• ### Math: gregorian date to day number?

not acceptable: julian day number calculations. rules are provided here:http://www.sizes.com/time/cal_gregorian.htm you can code in javascript, c, or autoit, or maybe pseudocode. this is not for a college project. I am stumped trying to produce appropriate math to convert gregorian day number to date and back. I have this: func... show more
not acceptable: julian day number calculations. rules are provided here:http://www.sizes.com/time/cal_gregorian.... you can code in javascript, c, or autoit, or maybe pseudocode. this is not for a college project. I am stumped trying to produce appropriate math to convert gregorian day number to date and back. I have this: func GregorianToDtime(\$Y,\$Mo,\$D,\$H,\$Mi,\$S,\$ms... byref \$dtime) ;do we have to offset these by 1? ;-----function good to 100,000 years if I coded it right. ;-----we will allow for a zero year. ;-----given gregorian date, convert to gregorian day number, then to dtime. local \$days= mod(\$Y,4)*365*\$Y ;Every year whose number is not divisible by 4 without remainder, consists of 365 days; ;\$days+=ceil((mod(\$Y,4) * mod(\$Y,100)>0)) * 366 * \$Y ;this doesn't end up 1 when any mods are zeros! ;every year which is so divisible, but is not divisible by 100, of 366; ;\$days+=((mod(\$Y,4) * mod(\$Y,100)>0)?1:0) * 366 * \$Y ;this doesn't end up 1 when any mods are zeros! ;every year which is so divisible, but is not divisible by 100, of 366; ;this language doesn't have a ternary operator,so we implement as an if statement local \$temp=0 if (mod(\$Y,4) * mod(\$Y,100)>0) then ;this doesn't end up 1 when any mods are zeros! \$temp=1 endif \$days += \$temp * 366 * \$Y ;every year which is so divisible, but is not divisible by 100, of 366; \$days += (int(\$Y/100) - int(\$Y/400)) * 366; every year divisible by 100 but not by 400, again of 366. \$days += int(\$Y/4000) * 365 ;years divisible by 4000 should consist of 365 days. \$days += NumDaysInMonth( \$Y,\$Mo) \$days += \$D \$days -= 1 ;subtract 1 day so days start at 0 \$dtime = (\$days * 1000*60*60*24) + (\$H*1000*60*60) + (\$Mi*60*1000) + (\$S*1000) + \$ms return \$dtime endfunc ;http://www.sizes.com/time/cal_gregorian.... func DtimeToGregorian(\$dtime,byref \$Y,byref \$Mo,byref \$D,byref \$H,byref \$Mi,byref \$S,byref \$ms) ;do we have to offset these by 1? ;-----function good to 100,000 years if I coded it right. \$ms=Mod(\$dtime,1000) \$S=Mod(Int(\$dtime / 1000),60) \$Mi=Mod(Int(\$dtime / (1000*60)),60) \$H=Mod(Int(\$dtime / (1000*60*60)),24) local \$days = int(\$dtime / (1000*60*60*24)) \$days+=1 ;required for conversion due to offset of 1 day in gregorian calendar system ;-----determine the year, it's the biggest number local \$year=0, \$year365=int(\$days/365), \$year366=int(\$days/366) if (mod(\$year366,100) * mod(\$year366,400) > 0 or mod(\$year365,4) * mod(\$year366,100) > 0) then \$Y = int(\$days/366) \$days -= (\$Y*366) elseif (mod(\$year365,4) > 0 or mod(\$year365, 4000)>0) then \$Y = int(\$days/365) \$days -= (\$Y*365) endif local \$i,\$monthdays for \$Mo=12 to 1 step -1 \$monthdays = SumOfDaysUpTo1stDayOfMonthWithoutYear( \$Y,\$Mo) if (\$monthdays < \$days) then ;-----match! \$days-=NumDaysInMonth(\$Y,\$Mo) \$D=\$days exitloop endif next ;-----return an array structure containing the resulting DTime local \$a[8] \$a[0]=7 \$a[1]=\$Y \$a[2]=\$Mo \$a[3]=\$D \$a[4]=\$H \$a[5]=\$Mi \$a[6]=\$S \$a[7]=\$ms return \$a endfunc func LeapIndex(\$Y) if (0<>mod(\$Y, 4)) then return 0; elseif (0<>mod(\$Y, 100)) then return 1; elseif (0<>mod(\$Y, 400)) then return 0; else return 1; endif endfunc func NumDaysInMonth(\$Y,\$Mo) switch \$mo case 1,8,12 return 31 case 2 return LeapIndex(\$Y) + 28 case 3,5,7,10 return 31 case 4,6,9,11 return 30 endswitch endfunc func SumOfDaysUpTo1stDayOfMonthWithoutYear( \$Y,\$Mo) ;this is the sum of days up to 1st day of \$Mo local \$sum=0,\$i for \$i = 1 to \$Mo-1 \$sum += NumDaysInMonth(\$Y,\$Mo) next return \$sum+1 endfunc
1 answer · Mathematics · 5 years ago
• ### Can windows 7 retail full be installed as 32-bit or 64-bit? do you have that choice?

I am not talking about the OEM/System Builders edition that comes with a computer, I am talking about the retail edition you buy at the store. If you don't know for sure, don't answer. my guess is there is no such choice, and there is no such thing as a 32-bit or 64-bit edition of retail windows, it just adapts itself.
I am not talking about the OEM/System Builders edition that comes with a computer, I am talking about the retail edition you buy at the store. If you don't know for sure, don't answer. my guess is there is no such choice, and there is no such thing as a 32-bit or 64-bit edition of retail windows, it just adapts itself.
1 answer · Software · 7 years ago
• ### Does windows 7 32-bit have command.com (I know about cmd.exe)?

somebody with windows 7 please tell me before I go out and spend the money for a windows 7 box when I could be using XP instead for development. I need command.com you can tell if you have command.com by doing windows-logo-flag-key+R command Enter. and tell me if they brought back the Start|Run menu on 7 (they disabled it by default in Vista).... show more
somebody with windows 7 please tell me before I go out and spend the money for a windows 7 box when I could be using XP instead for development. I need command.com you can tell if you have command.com by doing windows-logo-flag-key+R command Enter. and tell me if they brought back the Start|Run menu on 7 (they disabled it by default in Vista). I know I can bring it back, I use it all the time on XP. but the thing I am most concerned about right now is command.com on 32-bit OS's. I know on 64-bit OS's you will never find command.com because microsoft doesn't build in command.com with that type of OS, only 32-bit OS's.
1 answer · Software · 8 years ago