{"id":2048,"date":"2024-01-14T02:09:00","date_gmt":"2024-01-14T10:09:00","guid":{"rendered":"https:\/\/gantovnik.com\/bio-tips\/?p=2048"},"modified":"2024-01-14T02:59:48","modified_gmt":"2024-01-14T10:59:48","slug":"405-cardioid-in-polar-coordinates-by-matplot-in-python","status":"publish","type":"post","link":"https:\/\/gantovnik.com\/bio-tips\/2024\/01\/405-cardioid-in-polar-coordinates-by-matplot-in-python\/","title":{"rendered":"#405 Cardioid in polar coordinates by matplotlib in python"},"content":{"rendered":"<p><a href=\"https:\/\/gantovnik.com\/bio-tips\/2024\/01\/405-cardioid-in-polar-coordinates-by-matplot-in-python\/ex405\/\" rel=\"attachment wp-att-2049\"><img data-recalc-dims=\"1\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2024\/01\/ex405.png?resize=640%2C480&#038;ssl=1\" alt=\"\" width=\"640\" height=\"480\" class=\"alignnone size-full wp-image-2049\" srcset=\"https:\/\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2024\/01\/ex405.png 640w, https:\/\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2024\/01\/ex405-480x360.png 480w\" sizes=\"(min-width: 0px) and (max-width: 480px) 480px, (min-width: 481px) 640px, 100vw\" \/><\/a><\/p>\n<p>A cardioid is a two-dimensional plane figure that has a heart-shaped curve described in polar coordinates by the equation r = 2a(1 + cos \u03b8) for 0 \u2264 \u03b8 \u2264 2\u03c0:<\/p>\n<pre class=\"brush: python; title: ; notranslate\" title=\"\">\r\nimport numpy as np\r\nimport matplotlib.pyplot as plt\r\ntheta = np.linspace(0, 2.*np.pi, 1000)\r\na = 1.0\r\nr = 2 * a * (1. + np.cos(theta))\r\nplt.polar(theta , r)\r\nplt.savefig(&quot;ex405.png&quot;, dpi=100)\r\nplt.show()\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>A cardioid is a two-dimensional plane figure that has a heart-shaped curve described in polar coordinates by the equation r = 2a(1 + cos \u03b8) for 0 \u2264 \u03b8 \u2264 2\u03c0: import numpy as np import matplotlib.pyplot as plt theta = np.linspace(0, 2.*np.pi, 1000) a = 1.0 r = 2 * a * (1. + [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","_lmt_disableupdate":"yes","_lmt_disable":"","jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[56,69,2],"tags":[],"class_list":["post-2048","post","type-post","status-publish","format-standard","hentry","category-math","category-matplotlib","category-python"],"modified_by":"gantovnik","jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p8bH0k-x2","jetpack_likes_enabled":true,"jetpack-related-posts":[{"id":1754,"url":"https:\/\/gantovnik.com\/bio-tips\/2023\/01\/334-polar-plot-using-python\/","url_meta":{"origin":2048,"position":0},"title":"#334 Polar plot using python","author":"gantovnik","date":"2023-01-06","format":false,"excerpt":"ex334.py [code language=\"python\"] import numpy as np import matplotlib.pyplot as plt plt.axes(projection = 'polar') # creating an array # containing the angle values rads = np.arange(0,(2*np.pi),0.1) a=6 # plotting the cardioid for rad in rads: r = a*(1 + np.cos(rad)) plt.polar(rad,r,'ro',markersize=4) plt.savefig('ex334.png', dpi=72) plt.show() [\/code]","rel":"","context":"In &quot;matplotlib&quot;","block_context":{"text":"matplotlib","link":"https:\/\/gantovnik.com\/bio-tips\/category\/matplotlib\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2023\/01\/ex334.png?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":383,"url":"https:\/\/gantovnik.com\/bio-tips\/2019\/02\/annotating-text\/","url_meta":{"origin":2048,"position":1},"title":"#55 Annotating text in matplotlib plot","author":"gantovnik","date":"2019-02-12","format":false,"excerpt":"[code language=\"python\"] import os import matplotlib.pyplot as plt import numpy as np os.chdir(r'D:\\projects\\wordpress\\ex55') os.getcwd() fig = plt.figure() ax = fig.add_subplot(111) t = np.arange(0.0, 5.0, 0.01) s = np.cos(2*np.pi*t) line, = ax.plot(t, s, lw=2) ax.annotate('local max', xy=(2, 1), xytext=(3, 1.5), arrowprops=dict(facecolor='red', shrink=0.05), ) ax.set_ylim(-2,2) plt.savefig(\"example55.png\", dpi=100) plt.show() fig = plt.figure() ax\u2026","rel":"","context":"In &quot;python&quot;","block_context":{"text":"python","link":"https:\/\/gantovnik.com\/bio-tips\/category\/python\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2019\/02\/example64_1.png?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2019\/02\/example64_1.png?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2019\/02\/example64_1.png?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":1229,"url":"https:\/\/gantovnik.com\/bio-tips\/2021\/11\/210-parametric-curve-in-3d-2-2-2-2-2-2-2-2-2\/","url_meta":{"origin":2048,"position":2},"title":"#219 Polar plot legend","author":"gantovnik","date":"2021-11-28","format":false,"excerpt":"[code language=\"python\"] import matplotlib.pyplot as plt import numpy as np fig = plt.figure() ax = fig.add_subplot(projection=\"polar\", facecolor=\"lightgoldenrodyellow\") r = np.linspace(0, 3, 301) theta = 2 * np.pi * r ax.plot(theta, r, color=\"tab:orange\", lw=3, label=\"a line\") ax.plot(0.5 * theta, r, color=\"tab:blue\", ls=\"--\", lw=3, label=\"another line\") ax.tick_params(grid_color=\"palegoldenrod\") # For polar axes, it\u2026","rel":"","context":"In &quot;python&quot;","block_context":{"text":"python","link":"https:\/\/gantovnik.com\/bio-tips\/category\/python\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2021\/11\/ex219.png?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":2889,"url":"https:\/\/gantovnik.com\/bio-tips\/2024\/07\/440-cycloid-on-interactive-figure-with-widgets-in-python\/","url_meta":{"origin":2048,"position":3},"title":"#440 Cycloid on interactive figure with widgets in python","author":"gantovnik","date":"2024-07-21","format":false,"excerpt":"import numpy as np import matplotlib.pyplot as plt from matplotlib.widgets import Slider theta = np.linspace(0,2*np.pi) circ_x = lambda t: t + np.cos(theta) circ_y = 1 + np.sin(theta) cycl_x = lambda t: t - np.sin(t) cycl_y = lambda t: 1 - np.cos(t) t = 0 fig,ax = plt.subplots() plt.subplots_adjust(bottom=0.2) plt.ylim(0, 3)\u2026","rel":"","context":"In &quot;animation&quot;","block_context":{"text":"animation","link":"https:\/\/gantovnik.com\/bio-tips\/category\/animation\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2024\/07\/ex440.png?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2024\/07\/ex440.png?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2024\/07\/ex440.png?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":1980,"url":"https:\/\/gantovnik.com\/bio-tips\/2023\/12\/397-spiral-that-goes-around-circular-paraboloid-by-python\/","url_meta":{"origin":2048,"position":4},"title":"#397 Spiral that goes around circular paraboloid by python","author":"gantovnik","date":"2023-12-18","format":false,"excerpt":"[code language=\"python\"] import numpy as np import matplotlib.pyplot as plt fig = plt.figure() ax = plt.axes(projection='3d') # Surface ------------------ # Create the mesh in polar coordinates and compute corresponding Z r0 = 5 r = np.linspace(0, r0, 50) p = np.linspace(0, 2*np.pi, 50) R, P = np.meshgrid(r, p) Z =\u2026","rel":"","context":"In &quot;matplotlib&quot;","block_context":{"text":"matplotlib","link":"https:\/\/gantovnik.com\/bio-tips\/category\/matplotlib\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2023\/12\/ex397.png?fit=640%2C480&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2023\/12\/ex397.png?fit=640%2C480&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2023\/12\/ex397.png?fit=640%2C480&ssl=1&resize=525%2C300 1.5x"},"classes":[]},{"id":1226,"url":"https:\/\/gantovnik.com\/bio-tips\/2021\/11\/210-parametric-curve-in-3d-2-2-2-2-2-2-2-2\/","url_meta":{"origin":2048,"position":5},"title":"#218 Polar plot","author":"gantovnik","date":"2021-11-28","format":false,"excerpt":"[code language=\"python\"] import numpy as np import matplotlib.pyplot as plt r = np.arange(0, 2, 0.01) theta = 2 * np.pi * r fig, ax = plt.subplots(subplot_kw={'projection': 'polar'}) ax.plot(theta, r) ax.set_rmax(2) ax.set_rticks([0.5, 1, 1.5, 2]) # Less radial ticks ax.set_rlabel_position(-22.5) # Move radial labels away from plotted line ax.grid(True) ax.set_title(\"A line\u2026","rel":"","context":"In &quot;python&quot;","block_context":{"text":"python","link":"https:\/\/gantovnik.com\/bio-tips\/category\/python\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/gantovnik.com\/bio-tips\/wp-content\/uploads\/2021\/11\/ex218.png?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]}],"_links":{"self":[{"href":"https:\/\/gantovnik.com\/bio-tips\/wp-json\/wp\/v2\/posts\/2048","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gantovnik.com\/bio-tips\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gantovnik.com\/bio-tips\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gantovnik.com\/bio-tips\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gantovnik.com\/bio-tips\/wp-json\/wp\/v2\/comments?post=2048"}],"version-history":[{"count":3,"href":"https:\/\/gantovnik.com\/bio-tips\/wp-json\/wp\/v2\/posts\/2048\/revisions"}],"predecessor-version":[{"id":2052,"href":"https:\/\/gantovnik.com\/bio-tips\/wp-json\/wp\/v2\/posts\/2048\/revisions\/2052"}],"wp:attachment":[{"href":"https:\/\/gantovnik.com\/bio-tips\/wp-json\/wp\/v2\/media?parent=2048"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gantovnik.com\/bio-tips\/wp-json\/wp\/v2\/categories?post=2048"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gantovnik.com\/bio-tips\/wp-json\/wp\/v2\/tags?post=2048"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}