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Mike Huber wrote: |
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|
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> Hi, |
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> I'm just trying to do some quick calculations using bc, but the |
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> version installed through portage truncates on |
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> multiplication/division. It didn't used to do this 2 years ago when I |
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> was taking number theory, and there are no USE flags available for |
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> sys-devel/bc to change this. From the manpage: |
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> |
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> --------------------------------------------------------------------- |
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> |
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> The most basic element in bc is the number. Numbers are arbitrary |
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> precision numbers. This precision is both in |
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> the integer part and the fractional part. All numbers are |
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> represented internally in decimal and all computation is done in |
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> decimal. ( This version truncates results from divide and multiply |
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> operations.) There are two attributes of numbers, the length and the |
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> scale. The length is the total number of significant decimal digits |
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> in a number and the scale is the total number of decimal digits after |
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> the decimal point. For example: |
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> .000001 has a length of 6 and scale of 6. |
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> 1935.000 has a length of 7 and a scale of 3. |
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> |
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> |
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> ------------------------------------------------------------------------ |
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> |
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> |
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> Anyone have any ideas? |
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> |
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> --Mike |
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|
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Hi, |
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|
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Try this. |
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|
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$ echo '1/5' | bc |
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0 |
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$ echo '1/5' | bc -l |
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.20000000000000000000 |
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|
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I don't think bc has changed in a long time. |
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Maybe you forgot the -l option. |
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|
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You can also control the scale explicitly like this. |
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|
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echo 'scale=3;1/5' | bc -l |
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.200 |
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|
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Hope this helps. |
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|
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John Green |
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-- |
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