Small style change

Signed-off-by: Nicola Vigano <nicola.vigano@esrf.fr>

zUtil_Cryst/gtCrystTheta.m

-function theta = gtCrystTheta(dsp,energy)
+function [theta, sin_theta] = gtCrystTheta(dsp, energy)
 % GTCRYSTTHETA  Calculates theta angle given a list of d-spacing
-%     theta = gtCrystTheta(dsp,energy)
+%     theta = gtCrystTheta(dsp, energy)
 %     --------------------------------
 %    
 %     INPUT:
@@ -14,15 +14,9 @@ function theta = gtCrystTheta(dsp,energy)
 %
 %     Version 001 10-07-2013 by LNervo
 
+    lambda = gtConvEnergyToWavelength(energy);
 
-if ~exist('energy','var') || isempty(energy)
-    load parameters
-    energy = parameters.acq.energy;
+    % theta from the Bragg's law
+    sin_theta = lambda ./ (2 .* dsp);
+    theta = asind(sin_theta);
 end
-
-lambda = gtConvEnergyToWavelength(energy);
-
-% theta from the Bragg's law
-theta = asind(lambda./(2*dsp));
-
-end % end of function