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@kor01
kor01 / 001_DBSCAN_clustering.txt
Last active August 30, 2017 00:16
[RoboND_segmentation] segmentation clustering #robotics
DBSCAN: Density-Based Spatial Clustering of Application with Noise
Assummes: known distance boundary but not number of clusters
Also named as: Euclidean Clustering
two hyper parameters:
maximum distance within cluster
minimum number of points in a cluster
@kor01
kor01 / 001_recongnition_overview.txt
Last active August 30, 2017 01:30
[RoboND_recognition] #recognition #robotics
purpose:
to give each cluster in segmentation output a label
s.t. the grounding geometric specification of semantic command can be extracted
@kor01
kor01 / 01_color_select.py
Last active September 9, 2017 02:57
[CarND_find_lane] #self_dirving #perception
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import numpy as np
# Read in the image
image = mpimg.imread('test.jpg')
# Grab the x and y size and make a copy of the image
ysize = image.shape[0]
xsize = image.shape[1]
@kor01
kor01 / back_prop.txt
Last active September 19, 2017 13:35
[neural_nets_mind_bugs] #neural_nets #mind_bugs
in conventional notations:
1. layer input = the tensor before activation
2. layer output = the tensor after activation
3. next layer input = this layer output transformed by the edges
4. delta_layer = dLoss / dlayer_input
@kor01
kor01 / conv_net.txt
Last active May 6, 2019 01:36
[neural net jargons] #neural_net
depth = number of channel
path / kernel = [depth, convolutional sliding window weight]
sliding window weight = [height, width, depth], where depth equals to previous image channels
feature map_i = output[i, :, :] the ith layer of the output hyper image after convolution
stride = number of pixels when shifting the kernel window
valid_padding = stop slide at the edge (without padding)
same_padding = pad with zeros to make output image the same as input
@kor01
kor01 / construct_kinematics_frames.md
Last active October 25, 2017 01:29
[ros urdf] urdf files #ros #urdf

Definition and Conventions:

  • kinmematics frame of each link is infered rather than defined in urdf

  • each joint position and orientation is defined relative to it's parents kinematics frame

  • the parent kinematics frame is defined as the frame of it's parent joint

  • the kinematics frame of root link is eye(4)

@kor01
kor01 / plot_2d_polygon.m
Last active November 2, 2017 23:31
[matlab robotics] #robotics #matlab
hold on
plot(x(1, :), x(2,:))
@kor01
kor01 / add_bounding_box.py
Last active November 28, 2017 01:26
[CarND_classifiers] #CarND #classifiers
import numpy as np
import cv2
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
image = mpimg.imread('bbox-example-image.jpg')
# Define a function that takes an image, a list of bounding boxes,
# and optional color tuple and line thickness as inputs
# then draws boxes in that color on the output
@kor01
kor01 / save_session.py
Created November 28, 2017 05:25
[ipython] ipython tricks
%save my_useful_session 10-20 23
@kor01
kor01 / syms_assumption.m
Last active December 17, 2017 00:20
[matlab symbolic] symbolic computation in matlab #symbolic #matlab
% show current assumptions
syms z
assumptions(z)
% set assumptions
syms x
assume(x >= 0)
% add assumptions
assumeAlso(x,'integer')