cdm/src/main/java/ucar/unidata/geoloc/projection/AlbersEqualArea.java
private void precalculate() {

    double par1r = Math.toRadians(this.par1);
    double par2r = Math.toRadians(this.par2);

    if (Math.abs(par2 - par1) < TOLERANCE) {  // single parallel
      n = Math.sin(par1r);
    } else {
      n = (Math.sin(par1r) + Math.sin(par2r)) / 2.0;
    }

    double c2 = Math.pow(Math.cos(par1r), 2);
    C = c2 + 2 * n * Math.sin(par1r);
    rho0 = computeRho(lat0);

  }
private void precalculate() {

    double par1r = Math.toRadians(this.par1);
    double par2r = Math.toRadians(this.par2);

    if (Math.abs(par2 - par1) < TOLERANCE) {  // single parallel
      n = Math.sin(par1r);
    } else {
      n = (Math.sin(par1r) + Math.sin(par2r)) / 2.0;
    }

    double c2 = Math.pow(Math.cos(par1r), 2);
    C = c2 + 2 * n * Math.sin(par1r);
    rho0 = computeRho(lat0);

  }
Precalculate some stuff