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Y1=max(A,£Û£Ý,2) £ÛY2,K£Ý=min(A,£Û£Ý,2) Y3=max(A) £ÛY4,K1£Ý=min(A) ymax=max(max(A)) ymin=min(min(A)) ³ÌÐòÖ´Ðкó£¬ÔËÐнá¹ûΪ Y1 = 12 23 18 45 Y2 = -24 -4 -3 -7 K = 4 1 2 4 Y3 = 4523186 Y4 = -4-36-24 K1 = 2311 ymax = 45 ymin = -24 3. ͬά¶ÈÏòÁ¿/¾ØÕóµÄ±È½Ï ¶ÔÓÚÏàͬά¶ÈµÄÏòÁ¿»ò¾ØÕó£¬Ò²¿ÉÒÔÓÃmax£¨x£©ºÍmin(x)º¯ÊýÇó×î´óÖµºÍ×îСֵ£¬µ÷ÓøñʽÈçÏ£º Y = max(A,B) Y = min(A,B) ¡¾Àý3ª²11¡¿ÒÑÖª¾ØÕóAºÍB£¬ÇóÆä¶ÔÓ¦ÔªËØ×î´óÖµºÍ×îСֵ¡£ A=1216-24 -423120 2-3186 451310-7£¬B=211-624 -143227 21-13816 513-1017 ³ÌÐòÈçÏ£º A=£Û12 1 6 -24;-4 23 12 0;2 -3 18 6;45 13 10 -7£Ý; B=£Û2 11 -6 24;-14 3 22 7;21 -13 8 16;5 13 -10 17£Ý; Y1=max(A,B) Y2=min(A,B) ³ÌÐòÖ´Ðкó£¬ÔËÐнá¹ûΪ Y1 = 1211624 -423227 21-31816 45131017 Y2 = 21-6-24 -143120 2-1386 513-10-7 3.2.2Çó¾ØÕóµÄƽ¾ùÖµºÍÖÐÖµ Çó¾ØÕóµÄËãÊõƽ¾ùÖµ¿ÉÒÔµ÷ÓÃmeanº¯Êý£¬ÇóÖÐÖµ¿ÉÒÔµ÷ÓÃmedianº¯Êý£¬µ÷ÓøñʽÈçÏ£º y=mean(X)%·µ»ØÏòÁ¿µÄËãÊõƽ¾ùÖµ y=median(X)%·µ»ØÏòÁ¿µÄÖÐÖµ Y=mean(A) %·µ»Ø¾ØÕóÿÁеÄËãÊõƽ¾ùÖµµÄÐÐÏòÁ¿ Y=median(A) %·µ»Ø¾ØÕóÿÁеÄÖÐÖµµÄÐÐÏòÁ¿ Y=mean(A,dim) %dim=2ʱ£¬·µ»Ø¾ØÕóÿÐеÄËãÊõƽ¾ùÖµµÄÁÐÏòÁ¿;dim=1ʱ£¬Óëmean(A)ÍêÈ«Ïàͬ Y=median(A,dim)%dim=2ʱ£¬·µ»Ø¾ØÕóÿÐеÄÖÐÖµµÄÁÐÏòÁ¿;dim=1ʱ£¬Óëmedian(A)ÍêÈ«Ïàͬ ¡¾Àý3ª²12¡¿ÇóÏòÁ¿XºÍ¾ØÕóAµÄƽ¾ùÖµºÍÖÐÖµ¡£ X=£Û34,23,-23,4,76,58,10,35£Ý£¬A=1216-24 -423120 2-3186 451310-7 ³ÌÐòÈçÏ£º X=£Û34,23,-23,4,76,58,10,35£Ý; A=£Û12 1 6 -24;-4 23 12 0;2 -3 18 6;45 13 10 -7£Ý; y1=mean(X) y2=median(X) Y1=mean(A) Y2=median(A) Y3=mean(A,2) Y4=median(A,2) ³ÌÐòÖ´Ðкó£¬ÔËÐнá¹ûΪ y1 = 27.1250 y2 = 28.5000 Y1 = 13.75008.500011.5000-6.2500 Y2 = 7.00007.000011.0000-3.5000 Y3 = -1.2500 7.7500 5.7500 15.2500 Y4 = 3.5000 6.0000 4.0000 11.5000 3.2.3¾ØÕóÔªËØÇóºÍÓëÇó»ý ÏòÁ¿/¾ØÕóµÄÇóºÍ¿Éµ÷ÓÃsumº¯Êý£¬Çó»ý¿Éµ÷ÓÃprodº¯Êý£¬¾ßÌåµ÷ÓøñʽÈçÏ£º y = sum(x)%·µ»ØÏòÁ¿x¸÷ÔªËØÖ®ºÍ y = prod(x) %·µ»ØÏòÁ¿x¸÷ÔªËØÖ®»ý Y = sum(A)%·µ»Ø¾ØÕó¸÷ÁÐÔªËØÖ®ºÍµÄÐÐÏòÁ¿ Y = prod(A) %·µ»Ø¾ØÕó¸÷ÁÐÔªËØÖ®»ýµÄÐÐÏòÁ¿ Y = sum(A,dim)%dim=2ʱ£¬·µ»Ø¾ØÕó¸÷ÐÐÔªËØÖ®ºÍµÄÁÐÏòÁ¿;dim=1ʱ£¬Óësum(A)ÍêÈ«Ïàͬ Y = prod(A,dim) %dim=2ʱ£¬·µ»Ø¾ØÕó¸÷ÐÐÔªËØÖ®»ýµÄÁÐÏòÁ¿;dim=1ʱ£¬Óëprod(A)ÍêÈ«Ïàͬ ¡¾Àý3ª²13¡¿ÇóÏòÁ¿XºÍ¾ØÕóAµÄ¸÷ÔªËصĺÍÓë»ý¡£ X=£Û34,23,-23,4,76,58,10,35£Ý£¬A=1216-24 -423120 2-3186 451310-7 ³ÌÐòÈçÏ£º X=£Û34,23,-23,4,76,58,10,35£Ý; A=£Û12 1 6 -24;-4 23 12 0;2 -3 18 6;45 13 10 -7£Ý; y1=sum(X) y2=prod(X) Y1=sum(A) Y2=prod(A) Y3=sum(A,2) Y4=prod(A,2) ³ÌÐòÖ´Ðкó£¬ÔËÐнá¹ûΪ y1 = 217 y2 = -1.1100e+011 Y1 = 553446 -25 Y2 = -4320-897 12960 0 Y3 = -5 31 23 61 Y4 = -1728 0 -648 -40950 3.2.4¾ØÕóÔªËØÀÛ¼ÓºÍÓëÀ۳˻ý ÏòÁ¿/¾ØÕóÀۼӺͿɵ÷Óú¯Êýcumsum£¬À۳˻ý¿Éµ÷Óú¯Êýcumprod¡£¾ßÌåµ÷ÓøñʽÈçÏ£º y=cumsum(x) %·µ»ØÏòÁ¿xÀÛ¼ÓºÍÏòÁ¿ y=cumprod(x)%·µ»ØÏòÁ¿xÀ۳˻ýÏòÁ¿ Y=cumsum(A) %·µ»Ø¾ØÕó¸÷ÁÐÔªËØÀۼӺ͵ľØÕó Y=cumprod(A) %·µ»Ø¾ØÕó¸÷ÁÐÔªËØÀ۳˻ýµÄ¾ØÕó Y=cumsum(A,dim)%dim=2ʱ£¬·µ»Ø¾ØÕó¸÷ÐÐÔªËØÀۼӺ͵ľØÕó;dim=1ʱ£¬Óëcumsum (A)ÍêÈ«Ïàͬ Y=cumprod(A,dim) %dim=2ʱ£¬·µ»Ø¾ØÕó¸÷ÐÐÔªËØÀ۳˻ýµÄ¾ØÕó;dim=1ʱ£¬Óëcumsum (A)ÍêÈ«Ïàͬ ¡¾Àý3ª²14¡¿ÇóÏòÁ¿XºÍ¾ØÕóAµÄ¸÷ÔªËصÄÀÛ¼ÓºÍÓëÀ۳˻ý¡£ X=£Û3,2,-2,4,7,9,10,5£Ý£¬A=1216-24 -423120 2-3186 451310-7 ³ÌÐòÈçÏ£º X=£Û3,2,-2,4,7,9,10,5£Ý; A=£Û12 1 6 -24;-4 23 12 0;2 -3 18 6;45 13 10 -7£Ý; y1=cumsum(X) y2=cumprod(X) Y1=cumsum(A) Y2=cumprod(A) Y3=cumsum(A,2) Y4=cumprod(A,2) ³ÌÐòÖ´Ðкó£¬ÔËÐнá¹ûΪ y1 = 353714233338 y2 = 36-12-48-336-3024-30240-151200 Y1 = 1216-24 82418-24 102136-18 553446-25 Y2 = 12 1 6-24 -4823720 -96-6912960 -4320-897129600 Y3 = 121319-5 -4193131 2-11723 45586861 Y4 = 121272-1728 -4-92-11040 2-6-108-648 455855850-40950 3.2.5±ê×¼·½²îºÍÏà¹ØϵÊý 1. ±ê×¼·½²î ¶ÔÓÚ¾ßÓÐN¸öÔªËصÄÊý¾ÝÐòÁÐx1,x2,x3,¡­,xN£¬±ê×¼·½²î¿ÉÒÔÓÉÏÂÁÐÁ½ÖÖ¹«Ê½¼ÆË㣺 S1=1N-1¡ÆNi=1(xi-x-)2 »ò S2=1N¡ÆNi=1(xi-x-)2 ÆäÖÐ x-=1N¡ÆNi=1xi ¼ÆËãÏòÁ¿/¾ØÕóµÄ±ê×¼·½²îʱ£¬¿Éµ÷ÓÃstdº¯Êý£¬¾ßÌåµ÷ÓøñʽÈçÏ£º d=std(x)%ÇóÏòÁ¿xµÄ±ê×¼·½²î D=std(A,flag,dim) %Çó¾ØÕóAµÄ±ê×¼·½²î¡£dim=1ʱÇó¸÷ÁÐÔªËصıê×¼·½²î£¬dim=2ʱÇó¸÷ÐÐ %ÔªËصıê×¼·½²î;flag=0ʱ°´¹«Ê½¼ÆËã±ê×¼·½²îS1£¬flag=1ʱ°´¹«Ê½¼Æ %Ëã±ê×¼·½²îS2¡£Ä¬ÈÏflag=0£¬dim=1 ¡¾Àý3ª²15¡¿ÇóÏòÁ¿XºÍ¾ØÕóAµÄ±ê×¼·½²î¡£ X=£Û3,2,-2,4,7,9,10,5£Ý£¬A=1216 -42312 2-318 ³ÌÐòÈçÏ£º X=£Û3,2,-2,4,7,9,10,5£Ý; A=£Û12 1 6;-4 23 12;2 -3 18£Ý; d=std(X) D1=std(A,0,1) D2=std(A,0,2) D3=std(A,1,1) D4=std(A,1,2) ³ÌÐòÖ´Ðкó£¬ÔËÐнá¹ûΪ d = 3.9188 D1 = 8.082914.00006.0000 D2 = 5.5076 13.5769 10.9697 D3 = 6.599711.43104.8990 D4 = 4.4969 11.0855 8.9567 2. 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