- ajouté le module astro et la fonction cat, mais tout deux ne fonctionnent pas encore

trigo2.lua

@@ -0,0 +1,90 @@
+-- 2e Essais de faire des fonctions trigos qui manque dans NodeMCU
+-- source pour sin&cos: https://www.esp8266.com/viewtopic.php?p=64415#
+-- source pour arcsin&arctan: http://www.electronicwings.com/nodemcu/magnetometer-hmc5883l-interfacing-with-nodemcu
+print("\ntrigo2.lua   zf180726.1149   \n")
+
+
+
+function sin(x)
+   local p=-x*x*x
+   local f=6
+   local r=x+p/f
+   for j=1,60 do
+      p=-p*x*x
+      f=f*2*(j+1)*(j+j+3)
+      r=r+p/f
+   end
+   return r
+end
+
+function cos(x)
+   return sin(math.pi/2-x)
+end
+
+function tan(x)
+   return sin(x)/cos(x)
+end
+
+
+
+
+pi = 3.14159265358979323846
+
+
+function arcsin(value)
+    local val = value
+    local sum = value 
+    if(value == nil) then
+        return 0
+    end
+-- as per equation it needs infinite iterations to reach upto 100% accuracy
+-- but due to technical limitations we are using
+-- only 10000 iterations to acquire reliable accuracy
+    for i = 1,10000, 2 do
+        val = (val*(value*value)*(i*i)) / ((i+1)*(i+2))
+        sum = sum + val;
+    end
+    return sum
+end
+
+function arctan(value)
+    if(value == nil) then
+        return 0
+    end
+    local _value = value/math.sqrt((value*value)+1)
+    return arcsin(_value)
+end
+
+function atan2(y, x)
+    if(x == nil or y == nil) then
+        return 0
+    end
+
+    if(x > 0) then
+        return arctan(y/x)
+    end
+    if(x < 0 and 0 <= y) then
+        return arctan(y/x) + pi
+    end
+    if(x < 0 and y < 0) then
+        return arctan(y/x) - pi
+    end
+    if(x == 0 and y > 0) then
+        return pi/2
+    end
+    if(x == 0 and y < 0) then
+        return -pi/2
+    end
+    if(x == 0 and y == 0) then
+        return 0
+    end
+    return 0
+end
+
+print("On voit que l'arc sinus est précis au 1/2% prêt !")
+print("sin(3.14/2): "..sin(3.14/2))
+print("pi/(arcsin(1)*2): "..pi/(arcsin(1)*2))
+
+
+
+