TheAlgorithms/Python · error · ValueError
x-values must be equally spaced according to step size.
Error message
x-values must be equally spaced according to step size.
What it means
Error "x-values must be equally spaced according to step size." thrown in TheAlgorithms/Python.
Source
Thrown at maths/numerical_analysis/adams_bashforth.py:65
x_initials: list[float]
y_initials: list[float]
step_size: float
x_final: float
def __post_init__(self) -> None:
if self.x_initials[-1] >= self.x_final:
raise ValueError(
"The final value of x must be greater than the initial values of x."
)
if self.step_size <= 0:
raise ValueError("Step size must be positive.")
if not all(
round(x1 - x0, 10) == self.step_size
for x0, x1 in zip(self.x_initials, self.x_initials[1:])
):
raise ValueError("x-values must be equally spaced according to step size.")
def step_2(self) -> np.ndarray:
"""
>>> def f(x, y):
... return x
>>> AdamsBashforth(f, [0, 0.2], [0, 0], 0.2, 1).step_2()
array([0. , 0. , 0.06, 0.16, 0.3 , 0.48])
>>> AdamsBashforth(f, [0, 0.2, 0.4], [0, 0, 0.04], 0.2, 1).step_2()
Traceback (most recent call last):
...
ValueError: Insufficient initial points information.
"""
if len(self.x_initials) != 2 or len(self.y_initials) != 2:
raise ValueError("Insufficient initial points information.")
x_0, x_1 = self.x_initials[:2]View on GitHub (pinned to f5988cc097)
Solutions
- Ensure consecutive x-values differ by exactly the given step size.
- Recompute x-values as x0 + i*step_size before calling the method.
When it happens
Trigger: Thrown at maths/numerical_analysis/adams_bashforth.py:65 when the library encounters an invalid state.
Common situations: See trigger scenarios.
AI-assisted analysis of TheAlgorithms/Python@f5988cc097 (2026-08-14).
Data as JSON: /api/errors/48feee07788fab9f.
Report an issue: GitHub.