crypto: stabilitycheck v1

Cryptocoin.py

@@ -5,6 +5,7 @@ from urllib import request
 import json, requests
 import time
 import random
+import statistics
 
 class Cryptocoin(object):
 	"""Voor al uw crypto currency advies."""
@@ -31,6 +32,14 @@ class Cryptocoin(object):
 		a = (sum_of_products - (sum_x * sum_y) / length) / (sum_x_squared - ((sum_x ** 2) / length))
 		b = (sum_y - a * sum_x) / length
 		return a, b
+		
+	#get the stability based on the standard deviation
+	#the closer to 1, the better. (can be < 0, by the way. sue me.)
+	def getCoinStability(self, history):
+		histMean = statistics.mean(history)
+		if(histMean == 0):
+			return 0
+		return 1 - (statistics.stdev(history) / histMean)
 	
 	def getCoinPrice(self, coinId, currencyId="USD", time="now"):
 				
@@ -74,7 +83,10 @@ class Cryptocoin(object):
 			growPercentageShortTerm = growFactorShortTerm / history[N_DATAPOINTS-1]
 		
 		growPercentage = growPercentageLongTerm*0.3 + growPercentageShortTerm*0.7 #weighted average
-		return growPercentage, history
+		
+		stability = self.getCoinStability(history)
+		
+		return growPercentage, stability, history
 		
 		#TODO:
 		# - iets met stabiliteit?
@@ -124,20 +136,19 @@ class Cryptocoin(object):
 					tempName   = coinlist[randIndex]["Name"]
 				
 				#analyse:
-				growPercentage, tempHistory = self.analyseCoin(tempId)
-				
+				growPercentage, stability, tempHistory = self.analyseCoin(tempId)
 
 				#For the first few iterations we're picky
-				if (growPercentage > 0.1):
+				if (growPercentage > 0.1 and stability > 0.5):
 					return (tempName + " (" + tempId + ") gaat to the moon!")
-				if (growPercentage > 0.06):
+				if (growPercentage > 0.06 and stability > 0.25):
 					return ("Ik zou zeker een paar " + tempName + " (" + tempId + ") kopen.")
 					
 				if (i > 2):
 					#Later, negative advices are also acceptable...
 					if (growPercentage < -0.2):
 						return ("Ik zou zeker " + tempName + " (" + tempId + ") afraden!")
-					if (growPercentage > 0.015):
+					if (growPercentage > 0.015 and stability > 0.15):
 						return ("Ken je " + tempName + " (" + tempId + ") al? Best leuk")
 				if(i > 4):
 					#After a while, we're happy to give less useful advice
@@ -204,7 +215,7 @@ class Cryptocoin(object):
 		
 		coinId = coinId.upper()
 		
-		growPercentage, dummy = self.analyseCoin(coinId)
+		growPercentage, stability, dummy = self.analyseCoin(coinId)
 		
 		if (growPercentage < -0.1):
 			yield from ctx.channel.send("Sell! Sell! Sell! " + coinId + " gaat erg slecht.")