[PATCH 1/2] Remove unused and buggy get_cylinder_used_gas_string() function

[Linus Torvalds]

From: Linus Torvalds <torvalds at linux-foundation.org>
Date: Tue, 5 Apr 2016 15:20:01 -0700
Subject: [PATCH 1/2] Remove unused and buggy get_cylinder_used_gas_string() function

It's good that this is unused, because it does the calculations wrong.

Due to the gas compressibility the gas use calculations should subtract
the gas_volume() values at the differing pressures, not the pressures
themselves.

Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
---

This just removes dead and broken code. It's entirely incidental, and just 
came about from me looking at the gas use code.

I started off fixing the broken function, and then noticed it wasn't 
actually used. Get rid of the cruddy broken thing.

 core/helpers.h    |  1 -
 core/qthelper.cpp | 31 -------------------------------
 2 files changed, 32 deletions(-)

diff --git a/core/helpers.h b/core/helpers.h
index f88da015cf48..b9f7f50ca2e9 100644
--- a/core/helpers.h
+++ b/core/helpers.h
@@ -16,7 +16,6 @@ QString get_depth_string(int mm, bool showunit = false, bool showdecimal = true)
 QString get_depth_unit();
 QString get_weight_string(weight_t weight, bool showunit = false);
 QString get_weight_unit();
-QString get_cylinder_used_gas_string(cylinder_t *cyl, bool showunit = false);
 QString get_temperature_string(temperature_t temp, bool showunit = false);
 QString get_temp_unit();
 QString get_volume_string(volume_t volume, bool showunit = false);
diff --git a/core/qthelper.cpp b/core/qthelper.cpp
index 1d39510880ac..a261cca388bf 100644
--- a/core/qthelper.cpp
+++ b/core/qthelper.cpp
@@ -626,37 +626,6 @@ QString get_weight_unit()
 		return QString("%1").arg(translate("gettextFromC", "lbs"));
 }
 
-/* these methods retrieve used gas per cylinder */
-static unsigned start_pressure(cylinder_t *cyl)
-{
-	return cyl->start.mbar ?: cyl->sample_start.mbar;
-}
-
-static unsigned end_pressure(cylinder_t *cyl)
-{
-	return cyl->end.mbar ?: cyl->sample_end.mbar;
-}
-
-QString get_cylinder_used_gas_string(cylinder_t *cyl, bool showunit)
-{
-	int decimals;
-	const char *unit;
-	double gas_usage;
-	/* Get the cylinder gas use in mbar */
-	gas_usage = start_pressure(cyl) - end_pressure(cyl);
-	/* Can we turn it into a volume? */
-	if (cyl->type.size.mliter) {
-		gas_usage = bar_to_atm(gas_usage / 1000);
-		gas_usage *= cyl->type.size.mliter;
-		gas_usage = get_volume_units(gas_usage, &decimals, &unit);
-	} else {
-		gas_usage = get_pressure_units(gas_usage, &unit);
-		decimals = 0;
-	}
-	// translate("gettextFromC","%.*f %s"
-	return QString("%1 %2").arg(gas_usage, 0, 'f', decimals).arg(showunit ? unit : "");
-}
-
 QString get_temperature_string(temperature_t temp, bool showunit)
 {
 	if (temp.mkelvin == 0) {
-- 
2.8.0.rc4.303.g3931579