hod code cleaned out

c_tools/hod/halo_concentration.c

@@ -0,0 +1,155 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+
+#include "header.h"
+
+double collapse_redshift(double z);
+double cvir_pnorm_g1,
+  cvir_sigma_g1;
+
+/* This calculates and tabulates the halo concentrations
+ * as a function of halo mass. Uses the "Bullock model", 
+ * described in a little more detail below.
+ */
+
+double halo_concentration(double m)
+{
+  static int flag=1,n,prev_cosmo=0;
+  static double *x,*y,*y2;
+  int i;
+  float x1,x2,cfac;
+  double a,dm,x3,x4;
+  FILE *fp;
+  char fname[1000];
+
+  if(flag || RESET_COSMOLOGY!=prev_cosmo)
+    {
+      MSTAR = mstar();
+      if(OUTPUT)
+	fprintf(stdout,"Calc cvir with DELTA_HALO= %f\n",DELTA_HALO);
+      prev_cosmo=RESET_COSMOLOGY;
+      n=50;
+      if(flag)
+	{
+	  x=dvector(1,n);
+	  y=dvector(1,n);
+	  y2=dvector(1,n);
+	}
+      cvir_pnorm_g1=SIGMA_8/sigmac(8.0);
+
+      flag=0;
+      
+      dm=(log(HOD.M_max)-log(1.0E8))/(n-1);
+      for(i=1;i<=n;++i)
+	{
+	  x[i]=exp((i-1)*dm+log(1.0E8));
+	  y[i]=cvir_model(x[i]);
+	  x[i]=log(halo_mass_conversion(x[i],&y[i],DELTA_HALO));
+	  y[i]=log(y[i]);
+	  //y[i] = log(10);
+	}
+      spline(x,y,n,1.0E+30,1.0E+30,y2);
+    }
+  cfac = 0.13*log10(m/1.0e12) + 0.125;
+  cfac = 1;
+  if(m>80*MSTAR) m=80*MSTAR;
+  m=log(m);
+  splint(x,y,y2,n,m,&a);
+  return(exp(a)*cfac);
+  
+}
+
+
+/* This is the cvir model, which should reproduce the results
+ * of cvir3.f, which can be obtained off James Bullock's web site.
+ *
+ * Basic idea; For a halo of mass M, find the collapse redshift
+ * of that halo be finding the redshift at which rms mass variance
+ * sigma(Mf) = DELTA_CRIT (using linear growth factor), where Mf is some
+ * fraction of the redshift zero halo mass.
+ *
+ * cvir = k*(1+z_coll(M*f))
+ *
+ * Model params:
+ *  - k = 3.12    - fitting parameter (taken from cvir3.f)
+ *  - f = 0.001   - fraction of halo mass that collapsed at z_coll
+ */
+
+double cvir_model(double mass)
+{
+  double cvir,z_coll,zbrent(),rad;
+  double k=3.12;
+  double f=0.001;
+ 
+  rad=pow(3.0*f*mass/(4.0*PI*OMEGA_M*RHO_CRIT),1.0/3.0);
+  cvir_sigma_g1=cvir_pnorm_g1*sigmac(rad);
+
+  if(collapse_redshift(0.0)<0)return(k);
+  z_coll=zbrent(collapse_redshift,0.0,200.0,1.0E-3);
+  cvir=k*(1+z_coll);
+  return(cvir);
+}
+
+/* This is the input function to find where sig(M)*D(z)-DELTA_CRIT = 0
+ * which is the redshift at which a halo of mass M collapsed.
+ */
+double collapse_redshift(double z)
+{
+  double D;
+  D=growthfactor(z);
+  return(cvir_sigma_g1*D-DELTA_CRIT);
+}
+
+/* Some quantities are specific to an overdensity of 200 (i.e., the Jenkins mass
+ * function and the halo bias relation of Tinker et al. )
+ * Specfically, these are actually for FOF 0.2 halos, for which 200 is the
+ * current best approximation. (Although Warren et al quotes 250, which is the most recent
+ * value.)
+ *
+ * Therefore, the halo concentrations for Delta=200 halos need to be easily 
+ * accessible for halo mass conversion of these quantities. The values are 
+ * tabulates here, as opposed to the above routine which tabulates the 
+ * concentrations for a user-specified overdensity.
+ */
+
+double halo_c200(double m)
+{
+  static int flag=1,n,prev_cosmo=0;
+  static double *x,*y,*y2;
+  int i;
+  float x1,x2;
+  double a,dm,x3,x4;
+  FILE *fp;
+  char fname[1000];
+
+  if(flag || RESET_COSMOLOGY!=prev_cosmo)
+    {
+      if(OUTPUT)
+	fprintf(stdout,"Calc cvir with DELTA_HALO= %f\n",200.0);
+      prev_cosmo=RESET_COSMOLOGY;
+      n=50;
+      if(flag)
+	{
+	  x=dvector(1,n);
+	  y=dvector(1,n);
+	  y2=dvector(1,n);
+	}
+      cvir_pnorm_g1=SIGMA_8/sigmac(8.0);
+
+      flag=0;
+      
+      dm=(log(HOD.M_max)-log(1.0E8))/(n-1);
+      for(i=1;i<=n;++i)
+	{
+	  x[i]=exp((i-1)*dm+log(1.0E8));
+	  y[i]=cvir_model(x[i]);
+	  x[i]=log(halo_mass_conversion(x[i],&y[i],200.0));
+	  y[i]=log(y[i]);
+	}
+    }
+  m=log(m);
+  splint(x,y,y2,n,m,&a);
+  return(exp(a));
+  
+}