S. Rols added keyword /constant to conv_ins routine

lamp_mac/ATOMS/conv_ins.pro

-FUNCTION conv_ins, w_in , pc, cutoff, intrange,W_FWHM=W_FWHM
+FUNCTION conv_ins, w_in , pc, cutoff, intrange,W_FWHM=W_FWHM,CONSTANT=CONSTANT
 ;+
 ;******* ********
 ;** User callable
@@ -10,16 +10,19 @@ FUNCTION conv_ins, w_in , pc, cutoff, intrange,W_FWHM=W_FWHM
 ;** y=(1/w.sqrt(pi/2))exp(-2(x-x0)^2/w^2)
 ;** output spectrum in wavenumbers
 ;** ------------------------------------------------------
-;** call is w2=conv_ins(w1,0.05, 1.5, 3.0)
+;** call is w2=conv_ins(w1,0.05, 1.5, 3.0, /constant)
 ;** w1 is workspace to be convoluted
 ;** 0.05 is width of Gaussian resolution, a % of energy transfer
 ;** 1.5 is a cutoff to prevent divergence at small E
 ;** intrange is to integrate over the whole Gaussian
+;** /constant indicates that pc is not a percentage but a value of FWHM constant over the total range
+;** W_FWHM is the workspace number where the evolution of the FWHM as a function of energy is stored (useful for TOF)
 ;-
 
 ; modified 20/8/2008 to loop through a 2d array, energy along x
 ; comment 7/10/2008 needs further modification to work on 1D arrays
 ; done 13/3/2009
+; Modified by SR 01/2016 to include /constant keyword and W_FWHM option
 
 
 take_datp, datp & w_out = w_in & w_temp1=w_in[*,0] & w_temp2=w_in[*,0]
@@ -50,10 +53,14 @@ w_temp1=w_in[*,i_q]
 for i_orig=0,N-1 do begin
  ;define Gaussian, wd is width, pc is pcage of energy transfer, 1.17741 is sqrt(2ln2)
  ;0.79788 is pre-exp to give unit intensity, pc=0.02 read as parameter
-if (not i_fromwksp) then wd=e_i[i_orig]*pc/1.177410 else wd=w_fromwksp[i_orig]/1.177410
+if (not i_fromwksp) then begin
+if (keyword_set(CONSTANT)) then wd=pc/1.177410 else wd=e_i[i_orig]*pc/1.177410 
+endif else wd=w_fromwksp[i_orig]/1.177410
+
   if (wd LT w_cutoff) then begin
   wd=w_cutoff
   endif
+
  ;select range for intrangeation, intrange=3.0 read as parameter
  grange=intrange*wd/e_step &  igrange=floor(grange)
 ;print, igrange