From 6c9daa4f471ac90ffce3bfe8876c9008f79a5b7f Mon Sep 17 00:00:00 2001 From: Keith Packard Date: Sun, 13 Jul 2014 20:40:40 -0700 Subject: [PATCH] ao-tools: Provide altitude to temperature conversion function This takes altitude and computes the 'normal' temperature for that. Signed-off-by: Keith Packard --- ao-tools/lib/cc-convert.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/ao-tools/lib/cc-convert.c b/ao-tools/lib/cc-convert.c index 8d6876a0..b82dd778 100644 --- a/ao-tools/lib/cc-convert.c +++ b/ao-tools/lib/cc-convert.c @@ -108,6 +108,29 @@ 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 */ -- 2.30.2