X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=ao-tools%2Flib%2Fcc-convert.c;h=0f7fa809ecd77864be20d5b866529f7c1c082308;hb=1085ec5d57e0ed5d132f2bbdac1a0b6a32c0ab4a;hp=8d6876a064422a202fd7d3de99ea6ecd3cc4174e;hpb=9856b7c4397afcecc8f541af9a83824e817b3612;p=fw%2Faltos

diff --git a/ao-tools/lib/cc-convert.c b/ao-tools/lib/cc-convert.c
index 8d6876a0..0f7fa809 100644
--- a/ao-tools/lib/cc-convert.c
+++ b/ao-tools/lib/cc-convert.c
@@ -3,7 +3,8 @@
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; version 2 of the License.
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -108,6 +109,29 @@ cc_altitude_to_pressure(double altitude)
    return pressure;
 }
 
+double
+cc_altitude_to_temperature(double altitude)
+{
+
+   double base_temperature = LAYER0_BASE_TEMPERATURE;
+   double temperature;
+
+   int layer_number; /* identifies layer in the atmosphere */
+   double delta_z; /* difference between two altitudes */
+
+   /* calculate the base temperature for the atmospheric layer
+      associated with the inputted altitude */
+   for(layer_number = 0; layer_number < NUMBER_OF_LAYERS - 1 && altitude > base_altitude[layer_number + 1]; layer_number++) {
+      delta_z = base_altitude[layer_number + 1] - base_altitude[layer_number];
+      base_temperature += delta_z * lapse_rate[layer_number];
+   }
+
+   /* calculate the pressure at the inputted altitude */
+   delta_z = altitude - base_altitude[layer_number];
+   temperature = base_temperature + lapse_rate[layer_number] * delta_z;
+
+   return temperature - 273.15;
+}
 
 /* outputs the altitude associated with the given pressure. the altitude
    returned is measured with respect to the mean sea level */