First non zero integer

[Vincent Hazeleger]

Hi,

I have a sample with 667 variables. I want to replace the observations of variable 3 till variable 666 for the first non zero digit. The sample includes numbers like 0.005 or -45.6.

Can anyone help me? Trying it for 2 days now already.


Vincent

[William Lisowski]

Welcome to Statalist.

This seems to do what you want. The key was to convert the number to a string with a format that (I hope!) ensures that the first character in the string will be nonzero. Taking the absolute value prevents the minus sign, and "e" format ("scientific notation" to Boomer programmers) is intended to have the first significant digit left of the decimal point.

describe, simple
foreach var of varlist x2-x5 {
    generate byte d_`var' = real(substr(strofreal(abs(`var'),"%-9.3e"),1,1))
}
list, clean

. list, clean

       x1          x2          x3          x4         x5   d_x2   d_x3   d_x4   d_x5  
  1.    0   -.0700273   -.0508646    6.836784   986932.4      7      5      6      9  
  2.    0   -.0091926   -.4981204    73.49965     180984      9      4      7      1  
  3.    0   -.0448812    .4771252     96.8254   227689.7      4      4      9      2  
  4.    0   -.0867026   -.8328747   -11.71692   744834.1      8      8      1      7  
  5.    0   -.0204538   -.9097059   -63.65746   599702.2      2      9      6      6  
  6.    0    .0100857    .6076029    58.60998    55539.6      1      6      5      5  
  7.    0   -.0465563    .0217684    14.18886   184487.3      4      2      1      1  
  8.    0    -.030125    .3020099   -82.15974   918579.2      3      3      8      9  
  9.    0    .0636145     .337718   -22.57167   791856.8      6      3      2      7  
 10.    0    .0767329   -.0122538   -20.82788   26978.92      7      1      2      2

[Vincent Hazeleger]

Hi William,

You are my hero! It works perfect!

Thanks!!!