# Copyright 2021-2023 Ian Jauslin
# 
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# 
#     http://www.apache.org/licenses/LICENSE-2.0
# 
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import math

# sign function
def sgn(x):
    if x>=0:
        return 1
    return -1

# check whether a number is an integer (with tolerance)
def isint_nonzero(x):
    if abs(x)<1e-11:
        return False
    return abs(round(x)-x)<1e-11

# check that a number is in an interval
def in_interval(x,a,b):
    return x>=a and x<=b

# remove x from list a
def remove_fromlist(a,x):
    if x in a:
        a[a.index(x)]=a[len(a)-1]
        a=a[:len(a)-1]
    return a

# snap to a grid: ceiling
def ceil_grid(x,size):
    return math.ceil(x/size)*size
# snap to a grid: floor
def floor_grid(x,size):
    return math.floor(x/size)*size