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    If statement syntax error

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    • OkieWolf
      OkieWolf last edited by

      Agreed. It works fine if short and long are the same number, which equals 45 degrees.

      1 Reply Last reply Reply Quote 0
      • OkieWolf
        OkieWolf last edited by OkieWolf

        Here’s what I came up with. It’s much shorter and easier to understand and I GREATLY appreciate all the help and patience.
        This version does all the other one did plus more. This version will calculate the other side and angle based on two sides input and can now calculate any side of the triangle based on angle and any one of the three sides.

        def button3_tapped(sender):
        	hypotenuse = float(v['hypotenuse'].text or 0)
        	short = float(v['short'].text or 0)
        	long = float(v['long'].text or 0)
        	angle = float(v['angle'].text or 0)
        	if len([x for x in (hypotenuse, short, long, angle) if x]) != 2:
        		v['mess'].text = "Enter two fields"
        		v['mess'].background_color = 'red'
        		v['mess'].text_color = 'white'
        		return
        	if hypotenuse and not angle:
        		if short and not long:
        			v['long'].text = str(math.sqrt(hypotenuse ** 2 - short ** 2))
        			v['long'].text_color = 'green'
        			v['angle'].text = str(math.degrees(math.asin(short / hypotenuse)))
        			v['angle'].text_color = 'green'
        		elif long and not short:
        			v['short'].text = str(math.sqrt(hypotenuse ** 2 - long ** 2))
        			v['short'].text_color = 'green'
        			v['angle'].text = str(math.degrees(math.acos(long / hypotenuse)))
        			v['angle'].text_color = 'green'
        	else:
        		if not angle:
        			v['hypotenuse'].text = str(math.sqrt(short ** 2 + long ** 2))
        			v['hypotenuse'].text_color = 'green'
        			v['angle'].text = str(math.degrees(math.atan(short / long)))
        			v['angle'].text_color = 'green'
        		
        	if angle:
        		angle = math.radians(angle)
        		if short and not long and not hypotenuse:
        			v['hypotenuse'].text = str(short / (math.sin(angle)))
        			v['hypotenuse'].text_color = 'green'
        			v['long'].text = str(short / (math.tan(angle)))
        			v['long'].text_color = 'green'
        		elif long and not short and not hypotenuse:
        			v['hypotenuse'].text = str(long / (math.cos(angle)))
        			v['hypotenuse'].text_color = 'green'
        			v['short'].text = str(long * (math.tan(angle)))
        			v['short'].text_color = 'green'
        		elif angle and hypotenuse and not long and not short:
        			v['short'].text = str(hypotenuse * (math.sin(angle)))
        			v['short'].text_color = 'green'
        			v['long'].text = str(hypotenuse * (math.cos(angle)))
        			v['long'].text_color = 'green' 
        
        1 Reply Last reply Reply Quote 0
        • ccc
          ccc last edited by

          Please put the trailing three backticks on a line all by themselves.

          OkieWolf 1 Reply Last reply Reply Quote 0
          • OkieWolf
            OkieWolf @ccc last edited by

            @ccc
            Done

            1 Reply Last reply Reply Quote 0
            • ccc
              ccc last edited by

              OK. Now it is time to separate the business logic from the UI representation. We would need to put all the math logic in a function of the form:

              def triangle(a, b, hypotenuse=0, angle=45):
                  pass  # math logic goes here
              

              Where triangle(3, 4) returns (3, 4, 5.0, 45)
              Where triangle(3, 0) would raise ValueError()

              OkieWolf 1 Reply Last reply Reply Quote 0
              • JonB
                JonB last edited by

                It seems to me you could also dispense with most of the long / short specific logic, and just compute the other edge, then figure out which one is the long vs short after the fact.

                1 Reply Last reply Reply Quote 1
                • OkieWolf
                  OkieWolf @ccc last edited by OkieWolf

                  @ccc

                  Please explain

                  def triangle(a, b, hypotenuse=0, angle=45):
                      pass  # math logic goes here
                  Where triangle(3, 4) returns (3, 4, 5.0, 45)
                  Where triangle(3, 0) would raise ValueError() 
                  
                  1 Reply Last reply Reply Quote 0
                  • ccc
                    ccc last edited by

                    This was an invitation for you or someone else to write a function that can take between 2 and 4 parameters and calculate all other variables or raise an exception if there is no possible solution. This function would allow us to isolate all UI operations from all math operations. It would make it easier to test our math operations without the UI and would allow us to easily port the math operations to a different platform.

                    OkieWolf 2 Replies Last reply Reply Quote 0
                    • OkieWolf
                      OkieWolf @ccc last edited by OkieWolf

                      @ccc

                      Below will calculate short and long with given hypotenuse and angle but you have to enter zero for short and long input.

                      import math
                      
                      def triangle(short, long, hypotenuse, angle):
                          pass  
                          if hypotenuse and angle:
                          	angle = math.radians(angle)
                          	print ('Short = ' + str(hypotenuse * (math.sin(angle))))
                          	print ('Long = ' + str(hypotenuse * (math.cos(angle))))
                          	
                      triangle(0,0,10,30)
                      
                      1 Reply Last reply Reply Quote 0
                      • OkieWolf
                        OkieWolf @ccc last edited by

                        @ccc

                        This will calculate any side or angle. But input still has to be zero for unknowns at input.

                        import math
                        
                        def triangle(short, long, hypotenuse, angle):
                            pass
                            if len([x for x in (hypotenuse, short, long, angle) if x]) == 2:
                            	if hypotenuse and angle:
                            		angle = math.radians(angle)
                            		print	('Short = ' + str(hypotenuse * (math.sin(angle))))
                            		print	('Long = ' + str(hypotenuse * (math.cos(angle))))
                            	elif long and angle:
                            		angle = math.radians(angle)
                            		print	('Short = ' + str(long * (math.tan(angle))))
                            		print	('Hypotnuse = ' + str(long / (math.cos(angle))))
                            	elif short and angle:
                            		angle = math.radians(angle)
                            		print	('Long = ' + str(short / (math.tan(angle))))
                            		print	('Hypotnuse = ' + str(short / (math.sin(angle))))
                            	elif hypotenuse and short:
                            		print ('Long = ' + str(math.sqrt(hypotenuse ** 2 - short ** 2)))
                            		print ('Angle = ' + str(math.degrees(math.asin(short / hypotenuse))))
                            	elif hypotenuse and long:
                            		print ('Short = ' + str(math.sqrt(hypotenuse ** 2 - long ** 2)))
                            		print ('Angle = ' + str(math.degrees(math.acos(long / hypotenuse))))
                            	elif short and long:
                            		print ('Hypotenuse = ' + str(math.sqrt(short ** 2 + long ** 2)))
                            		print ('Angle = ' + str(math.degrees(math.atan(short / long))))
                            else:
                            	print ("ERROR")
                        
                        triangle(5,0,10,0) 
                        
                        1 Reply Last reply Reply Quote 0
                        • ccc
                          ccc last edited by ccc

                          Step 0: drop the pass line.
                          Step 1:

                              if len([x for x in (hypotenuse, short, long, angle) if x]) != 2:
                                  raise ValueError("Exactly two parameters must be zero.")
                          

                          Step 2: change triangle() so it never prints but instead returns the answer with the statement return short, long, hypotenuse, angle
                          Step 3: change triangle(5,0,10,0) to print(triangle(5,0,10,0)).

                          Step 1: is called a fast-fail which is safer and more readable than failing later in the function. Basically is says "I see a bad situation (bad input data) so I am going to raise an exception and stop processing".

                          mikael OkieWolf 2 Replies Last reply Reply Quote 0
                          • mikael
                            mikael @ccc last edited by

                            @ccc, I am sure I just saw you using count somewhere:

                            if (hyp, ...).count(0) != 2:
                                raise ...
                            
                            1 Reply Last reply Reply Quote 0
                            • OkieWolf
                              OkieWolf @ccc last edited by OkieWolf

                              @ccc

                              I don’t understand step 2

                              Step 2: change triangle() so it never prints but instead returns the answer with the statement return short, long, hypotenuse, angle.

                              Are you wanting me to change....
                              def triangle(short, long, hypotenuse, angle):

                              Also, changing to print(triangle(5,0,10,0)) adds “none” after returned values

                              1 Reply Last reply Reply Quote 0
                              • ccc
                                ccc last edited by ccc

                                def triangle(short, long, hypotenuse, angle):
                                    # Your code goes here...
                                    # Your code contains no print() calls.
                                    return short, long, hypotenuse, angle
                                
                                1 Reply Last reply Reply Quote 0
                                • cvp
                                  cvp last edited by cvp

                                  Your code contains no print() calls, like

                                          if hypotenuse and angle:
                                              angle = math.radians(angle)
                                              short = hypotenuse * math.sin(angle)
                                              long  = hypotenuse * math.cos(angle) 
                                  
                                  OkieWolf 1 Reply Last reply Reply Quote 0
                                  • OkieWolf
                                    OkieWolf @cvp last edited by

                                    @cvp

                                    I still don’t know what you’re wanting. My code has many print calls.
                                    Adding return short, long, hypotenuse, angle where you have it above won’t do anything because it’s part of the last elif. If I add it in line with def Tringle it errors.

                                    import math
                                    
                                    def triangle(short, long, hypotenuse, angle):
                                        pass
                                        if len([x for x in (hypotenuse, short, long, angle) if x]) == 2:
                                            if hypotenuse and angle:
                                                angle = math.radians(angle)
                                                print   ('Short = ' + str(hypotenuse * (math.sin(angle))))
                                                print   ('Long = ' + str(hypotenuse * (math.cos(angle))))
                                            elif long and angle:
                                                angle = math.radians(angle)
                                                print   ('Short = ' + str(long * (math.tan(angle))))
                                                print   ('Hypotnuse = ' + str(long / (math.cos(angle))))
                                            elif short and angle:
                                                angle = math.radians(angle)
                                                print   ('Long = ' + str(short / (math.tan(angle))))
                                                print   ('Hypotnuse = ' + str(short / (math.sin(angle))))
                                            elif hypotenuse and short:
                                                print ('Long = ' + str(math.sqrt(hypotenuse ** 2 - short ** 2)))
                                                print ('Angle = ' + str(math.degrees(math.asin(short / hypotenuse))))
                                            elif hypotenuse and long:
                                                print ('Short = ' + str(math.sqrt(hypotenuse ** 2 - long ** 2)))
                                                print ('Angle = ' + str(math.degrees(math.acos(long / hypotenuse))))
                                            elif short and long:
                                                print ('Hypotenuse = ' + str(math.sqrt(short ** 2 + long ** 2)))
                                                print ('Angle = ' + str(math.degrees(math.atan(short / long))))
                                        else:
                                            print ("ERROR")
                                    
                                    triangle(5,0,10,0)  
                                    
                                    cvp 1 Reply Last reply Reply Quote 0
                                    • cvp
                                      cvp @OkieWolf last edited by

                                      @OkieWolf I understand, I only want to show what @ccc adviced. The triangle code without any print and only one print of triangle results

                                      OkieWolf 1 Reply Last reply Reply Quote 0
                                      • OkieWolf
                                        OkieWolf @cvp last edited by OkieWolf

                                        @cvp

                                        I think I understand now. But I can’t get the indentation at “return” to stop erroring.

                                        import math
                                        
                                        def triangle(short, long, hypotenuse, angle):
                                            if len([x for x in (hypotenuse, short, long, angle) if x]) != 2:
                                                raise ValueError("Exactly two parameters must be zero.")
                                            if hypotenuse and angle:
                                            	angle = math.radians(angle)
                                            	print	('Short = ' + str(hypotenuse * (math.sin(angle))))
                                            	print	('Long = ' + str(hypotenuse * (math.cos(angle))))
                                            elif long and angle:
                                            	angle = math.radians(angle)
                                            	print	('Short = ' + str(long * (math.tan(angle))))
                                            	print	('Hypotnuse = ' + str(long / (math.cos(angle))))
                                            elif short and angle:
                                            	angle = math.radians(angle)
                                            	print	('Long = ' + str(short / (math.tan(angle))))
                                            	print	('Hypotnuse = ' + str(short / (math.sin(angle))))
                                            elif hypotenuse and short:
                                            	print ('Long = ' + str(math.sqrt(hypotenuse ** 2 - short ** 2)))
                                            	print ('Angle = ' + str(math.degrees(math.asin(short / hypotenuse))))
                                            elif hypotenuse and long:
                                            	print ('Short = ' + str(math.sqrt(hypotenuse ** 2 - long ** 2)))
                                            	print ('Angle = ' + str(math.degrees(math.acos(long / hypotenuse))))
                                            elif short and long:
                                            	print ('Hypotenuse = ' + str(math.sqrt(short ** 2 + long ** 2)))
                                            	print ('Angle = ' + str(math.degrees(math.atan(short / long))))
                                          return(short, long, hypotenuse, angle)
                                            	
                                        #triangle(5,0,10,0) 
                                        
                                        1 Reply Last reply Reply Quote 0
                                        • ccc
                                          ccc last edited by ccc

                                          from math import acos, asin, atan, cos, degrees, radians, sin, sqrt, tan
                                          
                                          
                                          def triangle(short, long, hypotenuse=0, angle=0):
                                              if (hypotenuse, short, long, angle).count(0) != 2:
                                                  raise ValueError("Exactly two parameters must be zero.")
                                              radians_angle = radians(angle)
                                              if short:
                                                  if long:
                                                      hypotenuse = sqrt(short ** 2 + long ** 2)
                                                      angle = degrees(atan(short / long))
                                                  elif hypotenuse:
                                                      long = sqrt(hypotenuse ** 2 - short ** 2)
                                                      angle = degrees(asin(short / hypotenuse))
                                                  else:  # short and angle
                                                      long = short / tan(radians_angle)
                                                      hypotenuse = short / sin(radians_angle)
                                              elif long:
                                                  if hypotenuse:
                                                      short = sqrt(hypotenuse ** 2 - long ** 2)
                                                      angle = degrees(acos(long / hypotenuse))
                                                  else:  # long and angle
                                                      short = long * tan(radians_angle)
                                                      hypotenuse = long / cos(radians_angle)
                                              else:  # hypotenuse and angle
                                                  short = hypotenuse * sin(radians_angle)
                                                  long = hypotenuse * cos(radians_angle)
                                              short, long, hypotenuse = sorted([short, long, hypotenuse])
                                              return float(short), float(long), float(hypotenuse), float(angle)
                                          
                                          
                                          # The result for each of these should be (3.0, 4.0, 5.0, 36.8698976458440x)
                                          print(triangle(3, 4))  # short and long
                                          print(triangle(3, 0, 5))  # short and hypotenuse
                                          print(triangle(0, 4, 5))  # long and hypotenuse
                                          print(triangle(0, 0, 5, 36.86989764584402))  # hypotenuse and angle
                                          
                                          1 Reply Last reply Reply Quote 1
                                          • ccc
                                            ccc last edited by ccc

                                            This post is deleted!
                                            cvp 2 Replies Last reply Reply Quote 0
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