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When I enter the code blow, I check it and get no errors in the HPPL editor. When I try to run it, however, I get a syntax error in line 51. It works in CPython.

Traceback (most recent call last):
File "<stdin>", line 51
SyntaxError: invalid syntax

Code:

#PYTHON name

# cubic

from math import *

# compute real or complex roots of cubic polynomial

def cubic( a2, a1, a0 ):

    global z1,z2,z3

    Q = (3*a1 - a2**2)/9

    R = (9*a1*a2 - 27*a0 - 2*a2**3)/54

    D = Q**3 + R**2                        # polynomial discriminant

    if (D >= 0):                           # complex or duplicate roots

        S = sgn(R + sqrt(D))*abs(R + sqrt(D))**(1/3)

        T = sgn(R - sqrt(D))*abs(R - sqrt(D))**(1/3)

        z1 = -a2/3 + (S + T)               # real root

        z2 = -a2/3 - (S + T)/2             # real part of complex root

        z3 = -a2/3 - (S + T)/2             # real part of complex root

        im = abs(sqrt(3)*(S - T)/2)        # complex part of root pair

    else:                                  # distinct real roots

        th = acos(R/sqrt( -Q**3))

        z1 = 2*sqrt(-Q)*cos(th/3) - a2/3

        z2 = 2*sqrt(-Q)*cos((th + 2*pi)/3) - a2/3

        z3 = 2*sqrt(-Q)*cos((th + 4*pi)/3) - a2/3

        im = 0

    return im                               # imaginary part

# sign of number

def sgn( x ):

    if x < 0.0:

        return -1

    return 1

print("solve: x^3 + a*x^2 + b*x + c = 0")

a,b,c = input("a,b,c? ").split(",")

a=int(a)

b=int(b)

c=int(c)

im = cubic( a, b, c )

if im != 0.0:

    print("{",f"{z1:6.4f}, {z2:6.4f} + {im:6.4f}j, {z3:6.4f} - {im:6.4f}j","}")

else:

    print("{",f"{z1:6.4f}, {z2:6.4f}, {z3:6.4f}","}")

#end

EXPORT cubic()

BEGIN

  PYTHON(name);

END;

I was able to reproduce your results.

BTW your code runs ok with python 3.9.4 on the pc after PPL wrapper code is removed.

My guess is that the hp prime python may not support the split and formatting codes,
but I will have to create some small programs to confirm or refute that theory.

What is the HPPL editor?

Thanks.

HP Prime Python (micro Python?) might not support f string

Try string interpolation with format(), or %

On Python 2.6:

>>> z1, z2, z3, im = 1,2,3,4
>>> print "{ %6.4f, %6.4f + %6.4fj, %6.4f - %6.4fj }" % (z1,z2,im,z3,im)
{ 1.0000, 2.0000 + 4.0000j, 3.0000 - 4.0000j }

HP-Prime python is micropython. (http://micropython.org/; https://docs.micropython.org)
Micropython is based on Python 3.4. (see Help > Tree > HP apps > Python app > OK, page 2)
You may check this:

Code:

from sys import *

print(version_info)

F-string literals have been added to python since python 3.6.
You can check more about it here (https://www.python.org/dev/peps/pep-0498/)
(from https://stackoverflow.com/questions/5040...yntaxerror)

(06-17-2021 08:48 AM)Liamtoh Resu Wrote: [ -> ]I was able to reproduce your results.

BTW your code runs ok with python 3.9.4 on the pc after PPL wrapper code is removed.

My guess is that the hp prime python may not support the split and formatting codes,
but I will have to create some small programs to confirm or refute that theory.

What is the HPPL editor?

Thanks.

From Home screen, press Shift then 1. Now press New and you're in the HPPL editor.

(06-17-2021 11:32 AM)Thomas_Sch Wrote: [ -> ]HP-Prime python is micropython. (http://micropython.org/; https://docs.micropython.org)
Micropython is based on Python 3.4. (see Help > Tree > HP apps > Python app > OK, page 2)
You may check this:

Code:

from sys import * print(version_info)

F-string literals have been added to python since python 3.6.
You can check more about it here (https://www.python.org/dev/peps/pep-0498/)
(from https://stackoverflow.com/questions/5040...yntaxerror)

OK, I changed the format statements to the old method. Now I get an error on the input() statement. I try to enter -2,1,-2 and it enters Ans-2 for the first number.

(06-17-2021 02:57 PM)toml_12953 Wrote: [ -> ]OK, I changed the format statements to the old method. Now I get an error on the input() statement. I try to enter -2,1,-2 and it enters Ans-2 for the first number.

You need to enter -2 with [2] [+/-] or [+/-] [2], not with [-] [2]. If you start the entry with an operator key (+, -, x, /) the Prime will assume you want to apply this operator to the previous result (Ans).

Here is a small python program that calculates the average of three numbers
entered by the user.

Code:

#PYTHON name

# avg3nr02

import math

def pintro():

  print("average three numbers")

def enter_3():

   a,b,c = input("a,b,c? ").split(",")

   print(" " + a + ", " + b + ", " + c)

   return (int(a)+ int(b) +int(c))/3

def pout():

   q = enter_3()

   print("the average is ",q)

pintro()

pout()

#end 

EXPORT avg3nr02()

BEGIN

  PRINT;

  PYTHON(name);

END;

And another version that provides formatted output.

Code:

#PYTHON name

# avg3nr03

import math

def pintro():

  print("average three numbers")

def enter_3():

   a,b,c = input("a,b,c? ").split(",")

   print(" " + a + ", " + b + ", " + c)

   return (float(a)+ float(b) + float(c))/3

def pout():

   q = enter_3()

   print("the average is {0:.5f}".format(q))

pintro()

pout()

#end 

EXPORT avg3nr03()

BEGIN

  PRINT;

  PYTHON(name);

END;

And thanks for the nomenclature for HPPL.

Thanks.

(06-17-2021 03:01 PM)Didier Lachieze Wrote: [ -> ]You need to enter -2 with [2] [+/-] or [+/-] [2], not with [-] [2]. If you start the entry with an operator key (+, -, x, /) the Prime will assume you want to apply this operator to the previous result (Ans).

You can also enter a space before [-] [2]

toml_12953

Liamtoh Resu

Albert Chan

Thomas_Sch

toml_12953

toml_12953

Didier Lachieze

Liamtoh Resu

Albert Chan