4

# diff requires input that is at least one dimensional

Package:

numpy

18118

Exception Class:

ValueError

## Raise code

```
if n < 0:
raise ValueError(
"order must be non-negative but got " + repr(n))
a = asanyarray(a)
nd = a.ndim
if nd == 0:
raise ValueError("diff requires input that is at least one dimensional")
axis = normalize_axis_index(axis, nd)
combined = []
if prepend is not np._NoValue:
prepend = np.asanyarray(prepend)
if prepend.ndim == 0:
shape = list(a.shape)
```

## Links to the raise (1)

https://github.com/numpy/numpy/blob/5f3c3181b5d8db0e430e5f605cc45c4392f04934/numpy/lib/function_base.py#L1258## Ways to fix

5

**Error Code:**

```
import numpy as np
arr = 1
diff1 = np.diff(arr) <- ValueError: diff requires input that is at least one dimensional.
print(diff1)
```

**Fix code:**

```
import numpy as np
arr = [1] <- Here you've to change it, array should be at least one dimension. So you have to insert a list or at least one-dimensional array.
diff1 = np.diff(arr)
print(diff1)
```

**Explanation:**

```
np.diff contain a part of code-
nd = a.ndim
if nd == 0:
raise ValueError("diff requires input that is at least one dimensional")
```

**If you input a number rather than a list or ndarray(where n = N) then, the value of nd would be 0 in code, which will raise an error.**

### Add a possible fix

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