Remove a letter at the beginning of a string only if it starts with a specific letter

[Agent1592]

Dear SAS Community:

I used stattransfer and it put v in front of all my ticker symbols.

I am trying to remove the letter v in front of the variable name.  So for example if the _NAME_ is "v88890" I would like to remove the "v" and _NAME_ to be "88890". However if _NAME_ is "B1HHK8" then nothing is removed. So v is removed only at the beginning of _NAME_. The length of _NAME_ is maximum of 6 characters.

How do I achieve these efficiently.

data have;
  infile datalines dsd truncover;
  input C1:MMDDYY8. _NAME_:$8. COL1:32.;
  format C1 MMDDYY8.;
  label _NAME_="NAME OF FORMER VARIABLE";
datalines4;
12/30/05,v88890,9.794
12/30/05,v83818,70.151
12/30/05,v17015,541.057
12/30/05,v56453,637.7
12/30/05,v65994,79.277
12/30/05,v92915,33.648
12/30/05,v63487,38.452
12/30/05,v14527,82708.5
12/30/05,v339429,341.40265309
12/30/05,B011MX,152.421
12/30/05,v55837,620.948
12/30/05,v91027,565.622
12/30/05,B1HHK8,2.861
12/30/05,B1SN2C,805.965
12/30/05,v55077,64.756
12/30/05,B1B59F,1037
12/30/05,B049FG,69.544779936
12/30/05,v17423,534.259
12/30/05,v88124,87.264
12/30/05,v302210,131.136
12/30/05,v37791,257.75040253
12/30/05,v307940,111.416
12/30/05,v65827,133.831
12/30/05,B0BHKX,20.020925945
12/30/05,v69417,133.4
12/30/05,v25703,373.8
12/30/05,B140VT,0.8659560285
12/30/05,v315395,51.922
12/30/05,v9315,618.4
12/30/05,v308266,221.547
12/30/05,B0XZZ5,481.655
12/30/05,v65611,536.353
12/30/05,v53160,332.652
12/30/05,v68295,45.755
12/30/05,v56692,81.114
12/30/05,v16877,11.823
12/30/05,v69116,35.815
12/30/05,B03105,14.151
12/30/05,v314231,551.815
12/30/05,B0CD5F,20.735094553
12/30/05,v96454,37.302
12/30/05,B01NJN,50.59851504
12/30/05,B0K32V,
12/30/05,B02WRR,70.861
12/30/05,v14699,103.252
12/30/05,B2PF6M,10992
12/30/05,v301974,44.628
12/30/05,v17665,183.436
12/30/05,B06FN1,828.23766499
12/30/05,v29050,85.106
12/30/05,B05L0T,21.85
12/30/05,v26150,371.7
12/30/05,B1VVM6,
12/30/05,v29743,110.275
12/30/05,v89750,4.950383
12/30/05,v317297,578.969
12/30/05,BRTL8Q,
12/30/05,v23034,1772.8
12/30/05,B0WM2V,87.098
12/30/05,v89626,2578.3
12/30/05,v332520,435.539
12/30/05,B4KHXB,1.896
12/30/05,v27817,29.137697
12/30/05,v67250,195.952
12/30/05,v79811,460.5
12/30/05,B3CG9C,38.132
12/30/05,B09BY4,331.4
12/30/05,v84354,836.38717513
12/30/05,B1G527,31.441
12/30/05,B0L2JD,53.901
12/30/05,v5806,45.767
12/30/05,B28TMS,160.118
12/30/05,v18036,1925.918
12/30/05,B1VWM1,131.067
12/30/05,B4KNNH,
12/30/05,B58HZJ,3192.833
12/30/05,B084LP,
12/30/05,v68165,27.047
12/30/05,v2826,5503.900456
12/30/05,v10229,70.198
12/30/05,v25025,18.786664884
12/30/05,v335631,100.18523453
12/30/05,B2Q4TN,46.801535251
12/30/05,B138NB,1336.9
12/30/05,B28B28,
12/30/05,BYY8NN,
12/30/05,BMH465,11.324
12/30/05,B0L4LM,51.006844736
12/30/05,BG86C0,0.614
12/30/05,v27336,
12/30/05,BMSKPJ,
12/30/05,BWC53H,
12/30/05,B7VSCF,
12/30/05,B7V2GY,
12/30/05,B9B3DY,
12/30/05,B1XZS8,30029.416288
12/30/05,BD0Q3L,2.197992
12/30/05,v2813,169.6
12/30/05,B3ZHFD,168.3
12/30/05,B085SD,1.433
;;;;

[Reeza]

if substr(_name_, 1, 1) = 'v' then _name_ = substr(_name_,2);

Or a better approach is to go back to your transpose step and and see if you can have the label transposed. I highly suspect the labels have the values you want since SAS variable names can't be numeric.

[ballardw · Accepted solution]

One way for the example data:

data have;
  infile datalines dsd truncover ;
  input C1:MMDDYY8. _NAME_:$8. COL1:32.;
  format C1 MMDDYY8.;
  label _NAME_="NAME OF FORMER VARIABLE";
  if _NAME_ =:'v' then _NAME_= substr(_NAME_,2);
datalines4;
12/30/05,v88890,9.794
12/30/05,v83818,70.151
12/30/05,v17015,541.057
12/30/05,v56453,637.7
;;;;
run;

There is a question of do you want to remove a capitol V as well?

The =:  in the If is asking does the value on the right of the =: start with the given string. The string can be longer or even another variable.

[ChrisNZ]

Function first() can also be used in place of substr( ,1,1)  or  =:  .

So many choices!

[ChrisBrooks]

You can also do it with a regular expression e.g.

data want(drop=prx);
	set have;
	if _n_=1 then do;
		retain prx;
		prx=prxparse("s/^v//");
	end;
	_name_=prxchange(prx,1,_name_);
run;