Final implementation of ionization process by electron impact.

Possibility to input initial species distributions (density, velocity
    and temperature) via an input file for each species.

New moduleRandom includes function to generate random numbers in
different ways (still uses) the implicit RANDOM_NUMBER().

src/modules/moduleInject.f90

@@ -174,21 +174,14 @@ MODULE moduleInject
 
     !Random velocity from Maxwellian distribution
     FUNCTION randomVelMaxwellian(self) RESULT (v)
-      USE moduleConstParam, ONLY: PI
+      USE moduleRandom
       IMPLICIT NONE
 
       CLASS(velDistMaxwellian), INTENT(in):: self
       REAL(8):: v
-      REAL(8):: x, y
       v = 0.D0
-      x = 0.D0
 
-      DO WHILE (x == 0.D0)
-        CALL RANDOM_NUMBER(x)
-      END DO
-      CALL RANDOM_NUMBER(y)
-
-      v = self%v + self%vTh*DSQRT(-2.D0*DLOG(x))*DCOS(2.D0*PI*y)
+      v = self%v + self%vTh*randomMaxwellian()
 
     END FUNCTION randomVelMaxwellian
 
@@ -208,6 +201,7 @@ MODULE moduleInject
       USE moduleSpecies
       USE moduleSolver
       USE moduleMesh
+      USE moduleRandom
       IMPLICIT NONE
 
       CLASS(injectGeneric), INTENT(in):: self
@@ -215,7 +209,6 @@ MODULE moduleInject
       INTEGER:: i!, j
       INTEGER, SAVE:: nMin, nMax !Min and Max index in partInj array
       INTEGER:: n
-      REAL(8):: rnd
       CLASS(meshEdge), POINTER:: randomEdge
 
       !Insert particles
@@ -243,8 +236,7 @@ MODULE moduleInject
 
       !$OMP DO
       DO n = nMin, nMax
-        CALL RANDOM_NUMBER(rnd)
-        randomX = INT(DBLE(self%nEdges-1)*rnd) + 1 
+        randomX = random(1, self%nEdges)
 
         randomEdge => mesh%edges(self%edges(randomX))%obj
         !Random position in edge