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POPython Float String Formatting Not Working Right
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copied!<p>I'm pretty sure that I'm doing this correctly but not getting the results that I expect from Python 2.7.3 string formatting mini-language. I'm trying to format the output of a float to 3 integer values and a varying number of decimal values. Everything works except the integer values.</p> <p>By itself, the following code works to get me 3 integer values...</p> <pre><code>num = 3 value = '{:03}'.format(num) returns '003' </code></pre> <p>And floats work...</p> <pre><code>num = 3.12345 value = '{:01.2f}'.format(num) returns '3.12' </code></pre> <p>However, combining the two does not seem to work properly. The decimal precision works, but the integer precision does not...</p> <pre><code>num = '3.12345' value = '{:03.2f}'.format(num) returns '3.12' instead of the expected '003.12' </code></pre> <p>The same is true if I try any of the following formats...</p> <pre><code>value = '{:03.02f}'.format(num) - or - value = '{0:3.2f}'.format(num) - or - value = '{:3.02f}'.format(num) - or - value = '{0:3.02f}'.format(num) - or - value = '{0:03.2f}'.format(num) - or - value = '{0:03.02f}'.format(num) - or - value = '{:0>3.2f}'.format(num) etc... Which all return the same '3.12' instead of '003.12' </code></pre> <p>If you're curious about what I'm doing for the varying / dynamic decimal precision, the point is to keep all the values the same length, but different sets of values may not have the same precision. So I take the smaller of the longest precision value or 10 and force the others to match like this..</p> <pre><code>from decimal import Decimal dVals = [ abs(Decimal(val1).as_tuple().exponent), # Get the number of decimal points abs(Decimal(val2).as_tuple().exponent), # "" "" abs(Decimal(val3).as_tuple().exponent), # "" "" abs(Decimal(val4).as_tuple().exponent), # "" "" ] p = max(dVals) # Get the largest value p = min(p, 10) # Get the smaller of the largest value or 10 vals = [val1, val2, val3, val4] for val in vals: value = '{:0>3.{prec}f}'.format(val, prec = p) # do whatever with value here... </code></pre> <p>Again, this all works perfectly, except that the integer value never returns with 3 precision places when I combine it with float precision. So all my efforts to ensure the values output with the same formatted length are all for naught. Ultimately, the output should look similar to...</p> <pre><code>'009.123456700' '180.101010101' '054.987654321' </code></pre> <p>Instead, it looks like this...</p> <pre><code>'9.123456700' '180.101010101' '54.987654321' </code></pre> <p>In other words, ugly. :-|</p> <p>At the very least, I would accept the following output...</p> <pre><code>' 9.123456700' '180.101010101' ' 54.987654321' </code></pre> <p>Any ideas what I'm doing wrong here? Your help is much appreciated!</p> <p>Regards,</p> <p>-RMWChaos</p>

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